Clark,
I'm with Bruce and many others. This is just stupid that Intel is not doing anything about it.
Again, we are experiencing USB 2.0 speed on a clean installed Windows 8. The generic driver does not properly support Intel's USB 3.0. Updating the chipset driver or storage matrix is not related to this, and it does squat.
Problem is that Intel is not releasing any USB 3.0 driver update for Windows 8.
I'm not saying this is 100% the case as you and a very lucky few seem to have no problems with it. It's very hard for me to believe that some people's Intel USB 3.0 is working properly at USB 3.0 speed (no cached speed or anything) without a hack in Windows 8.