Depends on A: what processor you're going to use, and B: what features you want.
ASUS used to be great for AMD boards, but a lot of people have been disspointed with them lately.
Giga-Byte sells some great boards, but you have to look at them closely because they're notorious for leaving out that one feature you want, making all the other great stuff worthless.
In the end, it's not a matter of which is better. You have to look at the boards themselves, spec wise, and see what fits your ticket best.
Either way, you're gonna get a board made in some Asian country with a manual that reads like a 4th-grader's essay for a japanese party.