Asus p8h67-v vs gigabyte ga-h67a-ud3h

They are similar the only reason to differentiate would be personal preference. The I7 2600K will not be able to overclock on a H67 board but you will be able to take advantage of the better HD3000 graphics on the K CPU.

Yep, H67 boards can only overclock the GPU portion. Also note that H67 can only use up to 1333MHz memory -- they cannot "overclock" it any faster like P67 boards can.