Wow, looks like you have your own way to cope with boredom
I never quite understood this desire to put 2 graphics board, one of those is already a monster in itself. But since that's where you are heading, have you considered a 4870x2 instead of two GTX 260? From what I've heard there are still issues with the latter, besides it'll be more expensive and there is less memory.
On the other hand it's nVidia, so if you need CUDA and so on... personally I've always preferred this brand, must come from how bad ATI was with drivers at the beginning, they are doing much better now.
