Mac pro future gpu support?

[TheLOGICalone]

I am waiting on the 2010 refresh mainly to have a 3.33 6 core so I can use the additional cores to help with logic studio and pro tools when they can take advantage of the extra horsepower, 6 mem slots would be nice too. But, I also like to play games in bootcamp, which is why I want the fastest processor. My question is: with the increasing power drawn by high end cards like the gtx 480 and 5890, how is the mac pros pci capabilities now and what do you think will be changed in 2010 and beyond as far as power and support for leading gpus in the next few years? Ie... 2 gtx 480s or 5890s?