I'm only considering the ASUS boards for a few reasons.. Ultimately I think all the launch P67 boards will achieve a similar OC. The reason I prefer the ASUS boards so far are due to the number of features like Bluetooth, Intel GigE, and 16+2 power phases (deluxe). I dislike buying in at launch BUT my sig rig mobo took a dump so the timing couldn't have been better.. I'm deciding between the P8P67 Deluxe and the WS Revolution for a little future proofing.
There are more things like number of SATA ports, diagnostic LED, MOBO power & reset buttons.. etc etc. Pay attention to how the board handles multiple GPU as SB is limited in this respect. No big real world differences I bet, but still worth noting when making a decision.