I checked them out at the Apple Store today. I was wondering the same thing and the answer is no they don't. I did see that they do remap the buttons for games but I forgot to test that. Didn't buy one yet because they don'thave the 16's yet.
I have an 8GB, and no, the buttons do not change orientation for anything outside of games. (See iLounge's 11 Things article to see the game orientation screen which shows before the game loads). In addition, it does have the nice feature where it changes the orientation correctly if you're left or right handed.
But for video or CoverFlow use, the buttons remain unchanged.