Updated July 3rd: The Scott catalogue number for this issue is 5202.
Updated April 26th: Here is the Digital Color Postmark for this issue: 
It measures 2.93″ x 1.38″. Here is the black-and-white pictorial: 
It measures 2.97″ x 0.48″.
Updated April 19th:
On May 23, 2017, in Concord, MA, the U.S. Postal Service® will issue the Henry David Thoreau stamp (Forever® priced at 49 cents), in one design, in a pressure-sensitive adhesive (PSA) pane of 20 stamps (Item 475100). The stamp will go on sale nationwide May 23, 2017.
With this stamp, the U.S. Postal Service celebrates writer, philosopher, and naturalist Henry David Thoreau (1817–1862) on the bicentennial of his birth. The stamp art is an oil-on-panel painting of Thoreau’s face based on a famous 1856 daguerreotype by Benjamin Maxham. On the right side of the stamp is Thoreau’s signature of his last name. Below the signature is a branch of sumac leaves. With Thoreau’s personal example of simple living, his criticism of materialism, and the timeless questions he raises about the place of the individual in society and humanity‘s role in the natural world, he continues to inspire new generations to assert their independence, reinterpret his legacy, and ask challenging questions of their own. The artist for this stamp was Sam Weber. Art director Greg Breeding designed the stamp.
Stamp Fulfillment Services will make an automatic push distribution to Post Offices™ of a quantity to cover approximately 30 days of sales.
How to Order the First-Day-of-Issue Postmark:
Customers have 60 days to obtain the first-day-of-issue postmark by mail. They may purchase new stamps at their local Post Office, at The Postal Store® website at usps.com/shop, or by calling 800-782-6724. They must affix the stamps to envelopes of their choice, address the envelopes (to themselves or others), and place them in a larger envelope addressed to:
FDOI – Henry David Thoreau Stamp
USPS Stamp Fulfillment Services
8300 NE Underground Drive, Suite 300
Kansas City, MO 64144-9900
After applying the first-day-of-issue postmark, the Postal Service™ will return the envelopes through the mail. There is no charge for the postmark up to a quantity of 50. There is a 5-cent charge for each additional postmark over 50. All orders must be postmarked by July 23, 2017.
Philatelic products for this stamp issue are as follows:
- 475106 Press Sheet with Die-Cut, $88.20
- 475110 Digital Color Postmark Keepsake, $11.95
- 475116 First-Day Cover, $0.93
- 475121 Digital Color Postmark, $1.64
- 475124 Framed Art, $39.95
- 475130 Ceremony Program, $6.95
- 475133 Panel, $10.95
Technical Specifications:
Issue: Henry David Thoreau Stamp
Item Number: 475100
Denomination & Type of Issue: First-Class Mail Forever
Format: Pane of 20 (1 design)
Series: N/A
Issue Date & City: May 23, 2017, Concord, MA 01742
Designer: Greg Breeding, Charlottesville, VA
Art Director: Greg Breeding, Charlottesville, VA
Typographer: Greg Breeding, Charlottesville, VA
Artist: Sam Weber, Brooklyn, NY
Modeler: Sandra Lane/Michelle Finn
Manufacturing Process: Offset, Microprint
Printer: Banknote Corporation of America
Printed at: Browns Summit, NC
Press Type: Alprinta 74
Stamps per Pane: 20
Print Quantity: 12,000,000 stamps
Paper Type: Phosphor Tagged Paper, Block Tag
Adhesive Type: Pressure-sensitive
Processed at: Banknote Corporation of America, Browns Summit NC
Colors: PMS 7591/Sienna, Cyan, Magenta, Yellow, Black
Stamp Orientation: Horizontal
Image Area (w x h): 1.42 x 0.84 in./36.07 x 21.34 mm
Overall Size (w x h): 1.56 x 0.98 in./39.62 x 24.89 mm
Full Pane Size (w x h): 7.25 x 7.25 in./184.15 x 184.15 mm
Press Sheets Size (w x h): 22.00 x 22.00 in./558.80 x 558.80 mm
Plate Size: 180 stamps per revolution
Plate Numbers: “B” followed by five (5) single digits
Marginal Markings:
Front: Plate numbers in two corners of pane
Back: © 2016 USPS • USPS logo • Plate position diagram • Barcode (475100) in upper right and lower left corners of pane • Promotional text
Updated March 27th: [USPS media advisory]
Writer, Philosopher and Naturalist Henry David Thoreau to be Commemorated on a Forever Stamp
WHAT:
First-Day-of-Issue dedication ceremony for the Henry David Thoreau Commemorative Forever stamp. The event is free and open to the public.
WHO:
- Massachusetts Executive Office of Energy and Environmental Affairs Secretary Matthew Beaton
- Massachusetts Department of Conservation and Recreation Commissioner Leo Roy
- U.S. Postal Service General Counsel and Executive Vice President Thomas J. Marshall
- Select Board Town of Concord Chair Michael Lawson
- Walden Woods Project Board Member/Environmentalist/Actor Ed Begley Jr.
WHEN: Tue., May 23 @ 11 a.m.
WHERE:
Walden Pond State Reservation Visitors Center
915 Walden St.
Concord, MA 01742
The public may RSVP online at usps.com/thoreau. Followers of the U.S. Postal Service’s Facebook page can view live streaming video of the event at facebook.com/USPS. The media is asked to share the news on Twitter and Instagram using the hashtag #ThoreauStamps.
BACKGROUND: The U.S. Postal Service celebrates writer, philosopher, and naturalist Henry David Thoreau (July 12, 1817 – May 6, 1862) on the bicentennial year of his birth. The stamp art is an oil-on-panel painting of Thoreau’s face based on a famous 1856 daguerreotype by Benjamin Maxham. On the right side of the stamp is Thoreau’s signature of his last name. Below the signature is a branch of sumac leaves.
With Thoreau’s personal example of simple living, his criticism of materialism, and the timeless questions he raises about the place of the individual in society and humanity’s role in the natural world, he continues to inspire new generations to assert their independence, reinterpret his legacy, and ask challenging questions of their own. Sam Weber of Brooklyn, NY, was the stamp artist. Art director Greg Breeding of Charlottesville, VA, designed the stamp.
Updated March 13th: The USPS says this stamp will be issued May 23rd in Concord, MA.
From the USPS, November 22nd, 2016:
With his personal example of simple living, his criticism of materialism and the questions he raises about the place of the individual in society and humanity’s role in the natural world, Henry David Thoreau (1817-1862) continues to inspire readers. For 26 months, Thoreau lived in a one-room house on a lake just outside his hometown of Concord, MA, writing prolifically while farming, reading, thinking, taking long walks and observing nature around him. “Walden,” the 1854 book he wrote about his experience, still holds the attention of readers by blending elements of numerous genres to create a complex, eclectic and unique work. Art director Greg Breeding designed this stamp with original art by Sam Weber. 
Comment:
The USPS honored Thoreau in 1967: 
On July 12, 2017, in Chadds Ford, PA, the U.S. Postal Service® will issue the Andrew Wyeth stamps (Forever® priced at 49 cents), in twelve designs, in a pressure-sensitive adhesive (PSA) pane of 12 stamps (Item 475000). The stamps will go on sale nationwide July 12, 2017.
This issuance includes 12 stamps that feature a detail of a different Andrew Wyeth painting. The paintings are: “Wind from the Sea” (1947), “Big Room” (1988), “Christina’s World” (1948), “Alvaro and Christina” (1968), “Frostbitten” (1962), “Sailor’s Valentine” (1985), “Soaring” (1942–1950), “North Light” (1984), “Spring Fed” (1967), “The Carry” (2003), “Young Bull” (1960), and “My Studio” (1974). The selvage shows a photograph of Wyeth from the 1930s. Art director Derry Noyes designed the pane.
Issue: Andrew Wyeth Stamps
Mastering a realistic style that defied artistic trends, Andrew Wyeth (1917-2009) created haunting and enigmatic paintings based largely on people and places in his life — a body of work that continues to resist easy or comfortable interpretation. Finding endless inspiration both in his hometown of Chadds Ford, PA, and in rural Maine, he scrutinized the lives, houses and personal belongings of people around him, sometimes painting their portraits but just as often using objects and places to represent them. 2017 is the centennial of Wyeth’s birth. With subtle symbolism and eerie implications, his work invites us to reinterpret his personal vision. Derry Noyes art directed and designed this pane of 12 stamps.
On June 14, 2017, in Hartford, WI, the U.S. Postal Service® will issue the Have a Ball! stamps (Forever® priced at 49 cents), in eight designs, in a pressure-sensitive adhesive (PSA) pane of 16 stamps (Item 474900). The Have a Ball! $7.84 pane of 16 stamps may not be split, and the stamps may not be sold individually. The stamps will go on sale nationwide June 14, 2017.
It measures 2.94″x1.18″.
On April 11, 2017, in Rochester, NY, the U.S. Postal Service will issue the Robert Panara two ounce rate mail use stamp (Nondenominated, priced at 70 cents) in one design, in a pressure-sensitive (PSA) pane of 20 stamps (Item 114000). The stamp will go on sale nationwide April 11, 2017.
WHAT:
BACKGROUND:
The U.S. Postal Service commemorates the 200th anniversary of Mississippi becoming the 20th state on Dec. 10, 1817. The Mississippi Statehood Forever stamp features a photograph taken by Lou Bopp in 2009. It shows a close-up of a musician’s hands as he plays his guitar. Mississippi is the birthplace of many legendary blues artists who created a uniquely American genre of music.
This stamp celebrates the 200th anniversary of Mississippi statehood. Mississippi became the 20th state on Dec. 10, 1817. The stamp features a 2009 photograph showing a close-up of a guitar player hands. Mississippi is the birthplace of many legendary blues artists who created a uniquely American genre of music. Among states, the Magnolia State is 32nd in size, and with nearly three million people, it ranks 31st in population. Art director Greg Breeding designed the stamp with an existing photo taken by Lou Bopp.
It measures 2.93″ x 1.38″. There is also a pictorial first-day postmark: 
Although it looks virtually identical, we’re told it measures 2.97″ x 1.48″.
When:
It measures 2.93″ x 1.38″.
Tuesday, May 2, 2017, 11 a.m.
Wednesday, March 1, 2017
It measures 2.95” x 1.32″. The B&W first-day cancel for this issue is the standard 4-bar “FIRST DAY OF ISSUE.” Here is the “special” postmark that local post offices may use: 
It measures 2.9” x 1.3″
On March 1, 2017, in Lincoln, NE, the U.S. Postal Service« will issue the Nebraska Statehood stamp (Forever« priced at 49 cents), in one design, in a pressure-sensitive adhesive (PSA) pane of 20 stamps (Item 474400).
This stamp celebrates the 150th anniversary of Nebraska statehood. Known for agriculture, the Cornhusker State became the 37th state on March 1, 1867. Nebraska photographer Michael Forsberg set up among prairie grasses on the riverbank between the small cities of Grand Island and Kearney to capture the image shown on the stamp. In the photograph, sandhill cranes fly low to scout for shelter from nighttime predators. This mid-migratory rest for half a million birds along the Platte River is unique to Nebraska. Forsberg captured this image as winter thawed into spring around the year 2000. Art director Derry Noyes designed the stamp using Forsberg existing photograph.
It measures 2.95” x 1.45.
On February 1, 2017, in Washington, DC, the U.S. Postal Service® will issue the Dorothy Height stamp (Forever® priced at 49 cents), in one design, in a pressure-sensitive adhesive (PSA) pane of 20 stamps (Item 474300).
From the USPS, November 22nd, 2016:
The 40th stamp in the Black Heritage series honors Dorothy Height (1912-2010), the tireless activist who dedicated her life to fighting for racial and gender equality. Although she rarely gained the recognition granted her male contemporaries, she became one of the most influential civil rights leaders of the 20th century. The stamp features artist Thomas Blackshear II gouache and acrylics on board portrait of Height. The painting is based on a 2009 photograph shot by Lateef Mangum. Art director Derry Noyes designed the stamp.
This stamp pays tribute to the beauty and importance of pollinators with stamps depicting two of our continent’s most iconic, the monarch butterfly and the western honeybee, each shown industriously pollinating a variety of plants native to North America. These particular species exemplify the ecological service provided by all pollinators, which include other insects, birds, and bats. Crop pollination by insects contributes approximately $15 billion of produce to the U. S. economy each year. Trending declines in their populations alert us that pollinators are helped by planting pollinator gardens with native flowers or heirloom varieties of fruits and vegetables. Art director Derry Noyes designed this stamp pane with existing photographs.
features a different illustration of main character Peter exploring and playing in his neighborhood while wearing his iconic red snowsuit. The images include: Peter forming a snowball, Peter sliding down a mountain of snow, Peter making a snow angel, and Peter leaving footprints in the snow. Art director Antonio Alcalá designed the stamps with Ezra Jack Keat’s original art.
The 2017 Christmas season will be celebrated with four new Forever stamps featuring images that illustrate four beloved Christmas carols: “Jingle Bells,” “Deck the Halls,” “Silent Night,” and “Jolly Old Saint Nicholas. ” Familiar lines from each song highlight the individual stamps. Shades of blue in the stamp backgrounds evoke the evening scenes from the four carols. This booklet of 20 stamps includes five of each design. The late Howard E. Paine was art director; artist Steve McCracken created the original art.
