[MRSallee]

Definitely in the right direction. I've never thought long about solving for car interfaces, but I'd probably keep a more visual interface around and build it with these shortcuts in mind -- a basic point and touch interface for new users, and more gesture-based control for people that learn the system.

I'd also probably not do more than three-finger combinations. One, two, and three finger controls are pretty easy. Four and five require some hand contortions on car-sized screens.