A picture of what is supposed to be an Asus P6X58 is floating around the Internet showing off tow of these high-speed ports. The chip behind them is the NEC µPD720200.
The new ports are blue instead of black (I wonder how that will work on the boards that have been making USB ports Yellow).
As of right now there are no available USB 3.0 devices but once there are more boards out that support the standard the devices will start hitting the shelves.
Interestingly the pictures also show SATA 6Gbps, but there is no mention on if this is using the same Marvell controller that is being removed from the P55 boards or now.

Take a look here