ive been on mac for about a month now
and i have to say that even the imac is a speed machine
mines a 2.16 g core 2 duo and it can outperform anything i have used especially when it comes to video rendering and encoding
the mac pro is drool worthy but i have a nice big digital screen and lots of desk space left over
the imac is not what it used to be (back in the blueberry and grape days)