Is there some reason I should get HDTV instead of a display?

[Jake]

Oh, and yes, I'm a mac fanboi, guilty.

No shame there! It's a good club to be a part of... And here - *chugs* *passes Kool-Aid*

For whatever reason the OS doesn't support having the sound output to both at once. I'm confident I'll find a way to map a hotkey so I can quickly switch them without going into a menu, or I'll find some software that will allow output to both. We'll see.

There is a program to run sound from multiple outputs. I don't know if this is what I'm thinking of, but try it and let me know. It's called Sound Source, click here to download it for free.

Good luck otherwise! I'm gonna be setting up a Mac-based HTPC in my townhouse this fall. Probably a G4 Mini as a server, streaming to an AppleTV as a cheapo front end. Front Row can't be beat (on the Mac at least) for simplicity.