Sata 3 is moot in my eyes, seeing as SSDs aren't even at the speed limit of Sata 2 (which is ~375mb/s), so why do we need Sata 3 (~750mb/s)? Only enthusiast boards support them, and very few mainstream boards, but the mainstream boards aren't fully there yet, with perhaps two Sata 3 ports, and Sata 3 drives being fairly expensive compared to their Sata 2 brethren.
USB3 is useless as well, since nothing that is standard uses it. Imo, once mp3 players, such as iPhones and iPods start using USB3, it won't be very popular. It has the same issue with motherboard availability, and having to sacrifice PCIe lanes.
The chipsets simply aren't ready for USB3.