Wonders of America and Super Heroes stamp sets

The Wonders of America stamp set feature 40 natural and man-made wonders selected from every region of the US. They were designed by Lonnie Busch, who also designed the GREETINGS FROM AMERICA stamps in 2002. I'm wondering if the kids would find it interesting to try to see all 40 wonders sometime or whether it's no longer exciting to try to visit every state. The USPS site also has additional Wonders of America items, for those of us who have trouble explaining to kids the difference between stamps and stickers, including the Wonders of American Coloring Postcards and stamps, a Postcard set with stamps and stickers, a Poster, and a Stickers and Stamps pack...

And if you like Super Heroes, the latest stamp sheet includes 20 DC Comics Super Heroes and Comic Books. There is also a set of 20 Super Hero postcards for those of us with kids who want to share the Super Heroes with their friends. I love the idea of having the kids send postcards to their friends and I can't wait until they can write them themselves.

Related post:

July 19, 2005 - Race to the Tower of Power - Spoiler?, on Super Hero play, the Backyardigans Super Hero episode, and resources on Super Hero play.