Yes both Asus and Gigabyte have a board prepared and there are reviews (professional) out on them. Imagine the boards to hit shelves any day now. You probobly should read the reviews about the limits on Pci-express lanes.
Wait they are on the shelves already.
I went back trying to find it myself but failed, sorry. I can tell you it was not an in depth review just listed and compared features between the asus and the gigabyte. There was a considerable variation in implimentation though and I won't spoil your fun by trying to pretend I remember. The only thing of interest was that the Asus was adding more PCI-express lanes with the addition of some proprietary control chip and despite this there were still limitations. The gigabyte board described is on sale at newegg.com but I don't see the asus one.