I was wondering if you have tried any of the Front ends, like AMP. I did see earlier that you were going to build your own front end. Did you ever get around to that?
I am a Mac user and would not like to go back to a Windows system. Plus, the idea of not being able to use my iTunes music sounds horrible. I'm about to start building my own carputer and would like to stick with a Mac Mini, especially since it will be a usable computer outside of its usage in the car.
And by the way, the setup looks amazing. Terrific job.