The PCI Special Interest Group has plans to take on the Thunderbolt standard developed by Intel, reports the EE Times, with a cabled version of PCI Express, which would offer up to 32Gbit transfer speeds.
The proposed standard will be based on PCI Express 3, packing four 8Gbit lanes into a single cable. The initial proposal suggests using copper wires, with a maximum transfer distance of 3m, matching Thunderbolt's wired distances. A future version of the standard using optical cabling and PCI Express 4 would potentially reach 16 giga-transfers per second. The cabling would likely be thinner, and flatter, than that use for Thunderbolt interconnects.
As the proposed standard is designed for computer systems and their peripherals, it's though that it would support up to 20W of power delivery. That would be enough for a large range of appliances to run on without the need for an external power source. Thunderbolt is able to provide up 10W of power, shared among all the devices connected to a single port (of which there could be several).
The proposed standard is still being worked on, with the hope of having products using it available in mid 2013, so Thunderbolt (and USB 3.0) have a fair stretch of uncontested time ahead of them, yet.