So I'm soon to be the proud owner of Two 6870s (long story). I do all my gaming in Windows and I usually wait for a few updates/price cuts to play the latest games, so Crossfire is definitely on the table. Obviously the 7970 ($600-700)is not OS X compatible yet, but while we're waiting I wanted to look at what Crossfire is capable of. Apparently the CF'd 6870x2 do VERY well compared to the single 7970! Look for 6870 CrossfireX (X2 is something else): BFBC2 Metro2033 Now if someone could just tell me if Audio on the HDMI works, I'd be in business!