Something to bear in mind if you're planning on serious overclocking is that all of these mobos use Foxconn sockets - dodgy pin contact and risk of burning up your shiny new i7.
On the plus side, all of the new Gigabyte P55A boards use Lotes sockets. DFI are also going Lotes exclusively, and EVGA have said they'll replace anything that burns up. On the other hand, Asus have said socket burn is excluded under their warranty (and deny condoning overclocking). MSI boards are actually built by Foxconn, so no luck their either.