Same thing here.
Q6600 @ 3.0Ghz
2 x 8800GTX
8GB DDR2
RAID 0 HD's
When playing skirmish with my buddy, I'm consistently at 10FPS, and changing settings doesn't affect it. It also doesn't matter if SLI is on or not, same FPS.
When in SLI, both GPUs are at about 40% usage, and when not in SLI, 80%
CPU is always at like 40%
I have the power available, but it won't use it. I wish it worked better