I'm pretty curious to know how the Mac and Windows versions will run too.
Everyone here talks about how Blizzard is the only big company to code games in both OpenGL and Direct3D allowing it to run natively in both Windows and OS X. However I have tried playing Warcraft 3 on both my Pentium 4 computer and my iMac G4. The Pentium 4 pretty much beat the G4 hands down, so my bet is that it'll still run faster on Windows.
I'll wait till the actual OS X port comes out first before commenting further though. (and yes, I do know that it's a native port.)
I understand that everyone is different, but here's just my own experience. Basically, I used to own a crappy Pentium 4 desktop with an outdated ATI 9600 card and used it all the way up to early 2008, before purchasing my Macbook Pro. Initially I was really happy with it, as I could finally play new games without having to set everything to low, and still achieving a pretty decent FPS (30 - 50). I thought that my Macbook Pro was the best investment ever.
That was until I finally decided to replace my desktop 2 months ago. Since I didn't think I'd be using it much I decided to go with cheaper parts. I replaced it with a Core 2 Quad processor with an ATI 5770 graphics card, and the cost of the whole rig totalled up to about US$600 without the monitor. Ever since then, I never wanted to game on my MBP again. Why would I, when my desktop runs every single game at max settings and still achieves 60 fps. Furthermore, these parts aren't particularly top of the line either. (as compared to a Core i7 860 + ATI 5870)
Bottom line, yes, most Macs are able to run games at decent settings while achieving decent FPS. However, PCs will still be the king in PC gaming as they will always be able to provide a far superior gaming experience at a much cheaper price.
What was the graphics card in the iMac G4 again?
Yea, thats right.