I found the Radioshack.com website now has the Esplora. Yesterday (Boxing Day - Dec. 26th) I went to my local store in Virginia, US, and bought one. The clerk stated he had them in stock for two weeks. The cost is $64.99 and they have a promotion - getting a $10 credit coupon with every $50 spent.
The board is bigger than I thougt at about 16 cm. In the box it also comes with a USB to microUSB cable to program it with, a bonus.
I'll be firing it up soon. I'd like to see if I can get it connected to a radio and battery pack to make it a portable controller. I'm hopeful Adafruit may have some projects posted after Radio Shack's exclusivity ends.
My unboxing blog post: The 21st Century Digital Home: The Arduino Esplora is Available from Radio Shack