Asus is good, but they typically have shit CSR (so I've read--personally, haven't had to deal with them, but YMMV).
I've been Gigabyte for my most recent 2-3 builds, though. Because I got a UD4 something back in 2009 as part of a Fry's bundle deal, and it was solid. Next mobo was solid, then the one after that.
Gigabyte has more coppers, or something. Anyway, I now tend to think of Gigabyte on the same tier as Asus, and also a bit cheaper, so that's where I'll by looking for Mobo. I'll look at MSI, too, as I had at least one good experience with them.