For anyone interested, the PC Demo can already be obtained through ausgamers.com, many people have already.
http://www.ausgamers.com/files/download/html/30227
and an alternate link
http://chonnom0.filezaru.com/BioShockPCDemo.zip
I'm downloading but at the speed its going right now I'll probably have the full game before the demo
Anyways, I skimmed through the 2K Forums (trust me, be glad the macrumors community is as great as it is
) and people are reporting the game is playable at 800x600 with high texture/high models and everything else on medium or off on a 6600GT, since the X1600 is slightly better than it, I'm thinking Bioshock will be just fine at 1024x768 with the same settings on X1600 Macs, especially after applying the ATI bioshock hotfix.
I'll report back with results on my C1D MBP when I get the demo or the full game, whichever comes first.
http://www.ausgamers.com/files/download/html/30227
and an alternate link
http://chonnom0.filezaru.com/BioShockPCDemo.zip
I'm downloading but at the speed its going right now I'll probably have the full game before the demo

Anyways, I skimmed through the 2K Forums (trust me, be glad the macrumors community is as great as it is

I'll report back with results on my C1D MBP when I get the demo or the full game, whichever comes first.