Found this map generator over at Paperback Writer and had some fun with it.
Okay, so states I've been to:
visited 20 states (40%)
Though, I don't see anything for Washington D.C. I've been there too.
If I include states where I've just been through an airport:
visited 24 states (48%)
Create your own visited map of The United States
visited 9 states (4%)
Create your own visited map of The World
Hmm...I'd say I have some more traveling to do. There is an awful lot of world out there I want to see!