http://en.wikipedia.org/wiki/USB_3.0#USB_3.0
"USB 3.0 is targeted at ten times the current bandwidth, reaching roughly 4.8 Gbit/s by utilizing two additional high-speed differential pairs for "Superspeed" mode, and with the possibility for optical interconnect."
4.8 Gigs/sec! Too bad commercial products will come out 2009 or 2010 though.