Here's what I think:
Mac - great...dare I say excellent for graphic design. The G4s are dope. Not very versatile though. Can't play CS on a Mac. :chuckles: Go to a graphic design company and you'll get laughed at for owning a pc.
PC - everybody uses PCs for 3D Animation. Macs are unheard of. More importantly, you can also run industry-standard programs like Quark, Photoshop, Illustrator, Premiere, ProTools, etc. on a pc. Oh, and did I mention it's Counter-Strike-friendly?