Very nice: Here would be my suggestions.
Save up a little more and replace the Athlon X2 with this
Athlon FX-55.
Replace the two 7900GTX's with two of these GeForce 7950GX2's. You can't go wrong with Quad SLi, although I don't know how comfortable you would be with having the same amount of dedicated video memory as system memory

.
It would cost about $200 more, but I think it would be worth it. You would also probably have to change your motherboard to make sure it can handle Quad SLi (few currently can) and you would probably want to check nVidia's site to see if they rank your PSU as Quad-SLi ready. But by the time you save up, DIY Quad SLi will probably be pretty common.
Sweet rig either way though. Before I go off to college I'm probably going to save up and build a monster like that too.
P.S. *drool*