No free lunch
This is the usual story about IO virtualization: one wire to rule them all. NextIO's claims are just like many others. Which unified wire do they use ? Looking at the management's background, I would say Infiniband since most of them comes from RIP Banderacom. However, doing the virtualization at the PCI Express level is a bad move as its flow-control is too tight to allow for contention. If they stretch that part of the spec, who knows what else they relax.
It's a crowded space, but I just don't get the PCI-E angle.