Asrock will support SLI,Crossfire. If you will upgrade the CPU to Ivy Bridge and a video card with PCIE 3.0 you will benefit the full speed of PCIE 3.0. With that Asus mobo you don't have these options.
I have it and love it. PCIE 3.0, supposed to be IVB compatible and wonderfully stable. Well, I have an i3 so I haven't tried OC stability, but it has every option under the sun for when I upgrade the CPU.