I love all my Macs, and will never own or build a PC ever again. That said, I would stay away from the new 27" iMac. They are having problems with the performance of it right now. I'd wait maybe and see what Apple does. I love my Macbook Pro's though, I have 2, a 15" and a new 17". I also have a Mac Pro desktop with 2 Cinema Displays. If you can swing an extra $500-$1000 I'd go for that. Mini i wouldn't really do either. I have a mini but use it for XBMC and it acts as a network for movies in my house.
If you can't swing these, i would get a 17" Macbook Pro. You'll love it. Trust me
