Got my board, RAM and PSU in so I did the build tonight. I am short one ASUS Matrix GTX580, so I did SLI with the ASUS 570's instead until I get the second Matrix, but I did put the Matrix in for a pic. Also haven't moved my drives from my current rig yet.
Specs...
Case: Corsair 650D
Processor: 3930K
Motherboard: ASUS Rampage IV Extreme X79
RAM: 32GB - 8 x 4GB Corsair Vengeance 1866
Video: 2 x ASUS GTX570 DirectCUII SLI (soon to be 2 x Matrix GTX580 - only have 1 so far)
PSU: Corsair AX1200
Cooler: Corsair H100
Drives:
Kingston HyperX 240GB 6Gb/s SSD
Samsung DVD-RW
2 x 300GB Velociraptor HD
1 x 2TB Western Digital Green HD
About the Rampage, there is one thing I wish they taken from the Maximus Extreme-Z board, the backlit ROG emblem in the middle of the board. Really sets it off on a side-window case. I also decided at last minute to use the Corsair case; I had intended to use the Cooler Master HAF-X case, but didn't realize until I opened it up that the side-fan hides the PSU, the video cards and a good part of the motherboard from view. You end up seeing the hard drives mostly. I am too proud of this rig to hide it. We'll see how the 650D performs, it obviously lacks airflow from the HAF-X, if it doesn't cool well enough, I'll swap it into the HAF-X or find another case that has a good side-view with equal cooling and 9 expansion slots.