Here's the authoratative source on what is and isn't available on which Nook device - the B&N website:
http://www.barnesandnoble.com/u/nook...you/379002498/
The info I supplied about pricing and features was based on a features comparison in an on-line review - but it was incorrect.
Nook color is $249, and has WiFi only - NO 3G (also has a 7" screen vs 6" for the B&W, but who gives a shit if it's less than 9", right?)
Nook B&W is $149 for the version with WiFi only, $199 for the version with WiFi AND 3G.
I apologize for the misinformation before. So among B&W devices with free 3G, the corresponding Nook and Kindle versions are only $10 apart. At that point it comes down to access to content (and the fact that the Nook has a touch screen and the Kindle doesn't).