Got a GoPro Hero 2 a few weeks ago. Very impressive bit of kit. Made a really nice aeros video with it. The motorsports edition comes with decent suction cup that stays on at +4 to -1 G. So far I have only used it inside the cockpit, but one day I might just go for the outside view...
There are ways to minimize the effect from rolling shutter but frankly it's just as easy to simply ignore it.
If you want to record intercom sound you need to buy an alternative case from GoPro that gives you access to the Mic In port. Or cut a hole in the default (waterproof) case.
Anyway, there's an article about this very subject in this months Flyer magazine.
Edited to add: This may be the solution to both problems:
PILOTS! Stop GoPro Hero Propeller Artifacting | The Pilot Report