Warning: Don't use these cheap USB hubs!
An inspection of the board reveals solder splashes and poor soldering. Use only brand name hubs (like Belkin) with 3 amp power supplies. Even if you don't use the power supply, I suspect that a manufacturer that uses an ample power supply has a better unit.
The power supply that comes with it is only rated at 1 amp - should by 3.5 amps (.5 amps per port 7 ports). And it wouldn't even power the Pi (.5 amp). I had switched the power supply to one that came with the Belkin hubs (3.5 amp) but bottom line is these hubs are no good.
They will back power the Pi through the hub's input port (usefull in this application, but a design defect).