That doesn't seem clear from the coverage so far. Obviously it has to be USB in the box, but the name hints that there would be a Thunderbolt option at least.
I'd be surprised. There's nothing you would need 10 Gbps for on a phone. The flash memory wouldn't even keep up. Plus with cables costing $50, it'd be an expensive option to have a second kind of cable. It's probably just marketing lingo to make it seem like it's related to TB.
Driving a display would be one of those times, though. I would love having a phone as the basic computing device, with a desktop and tablet shell.