I would stay away from ASUS, they are notorious for having problems with certain memory manufacturers. I would tend towards the Gigabyte boards, specificly the 975 chipsets. They allow higher OC's then SLI/CF boards and are solid. Plus, there is a rumour of Nvidia unlocking SLI on 975 chipsets (just a rumour so I wouldn't put too much weight behind it).
Another bonus is that Quad-core chips are supposed to be drop in compatible with Core 2 Duo motherboards. This is of course Intel PR, but just another thing to keep in mind.