Copy+Paste of my ideas of an Audiosurf App:
The pros to this idea:
* Everybody with an iPhone or iTouch probably has a decent sized music collection
* Audiosurf would become a lot more mainstream with the probable reaction from the iPhone/iTouch community
* Audiosurf would have to be rewritten for OS X with the iPhone SDK
Link to iPhone SDK Program: http://developer.apple.com/iphone/program/
While the majority of the Audiosurf community won't relate to this, that won't be a problem since the whole point of doing this would be to reach a larger music community.
Where it would be nigh impossible to run Audiosurf on an iPod, the SDK out for the iPhone makes it very possible. As far as writing Audiosurf for a DS goes, the publishing process would be much more complicated. With Apple's SDK Program, the developer could just send the program to them when its finished for:
-A much larger and interested community
-70% of the profit, and a much larger amount of money in the end.