Best USB 3.0 motherboard?

What's the best motherboard at the moment that supports USB 3.0?

Depends which CPU and which CPU socket. This is overall, price, performance and features etc. overall.

For X58, it's the ASUS P6X58D Premium - because it's the only one, AFAIK.

For P55, it's the ASUS P7P55D-E Pro or LX if you're not using more than one graphic card.

As for AMD chipsets - most 890GX chipset based motherboards support USB 3.0, and some newer 770 and 790X boards support it too.

ASUS customer support?

I know that the P7P55D-E Pro has obtained very good reviews, I'm not sure about the P6X58D Premium though - the board which you'd want if you want an i7 920, although it's better to get an i7 930.

i7 930/920 (LGA1366)+ P7P55D-E Pro (LGA1156) --> XXX
it doesn't match. i7 9xx needs a x58 chipset mobo. Buy the ASUS P6X58D PREMIUM. It's an amazing mobo and it has everything you can ask for.
If you want a P55 mobo, then buy a i7 8xx cpu.

what about the 96x58-e what makes it worse than the premium?

I own both the 920 and 930, they both have the same # of multipliers, 22.

Although i7 920 is $30 less than the 930, only goes for $260 on Amazon.com