Thanks for the warm welcome Alisa!
I knew before ordering my Kindle that I was out of EVDO range and would have to use USB. I ordered about 15 books Monday and didn't want to use up 20-40 Megs on my hard drive it would have consumed using USB. So yes, I've been using the USB cable since the get-go. And of course the wireless switch stays off unless I find myself in range.
Here's what the TSA has to say about the battery issue
and New York Times has this:
I agree with the first responder in the NYT article. The checkers will not understand the fine points of the rules, and will just throw out our valuable batteries. What a world!