PCIe is already a blazing fast interconnect technology, I can't imagine what kind of bus is going to be required to feed something this bandwidth-hungry.

"Meanwhile, designers have identified a handful of new features they will add to the 5-Gbit/s version. They include an access control feature to give software an ability to control packet routing on the interconnect and prevent hackers from spoofing and rerouting data, primarily for peer-to-peer traffic."