And yet another sign that Thunderbolt is stumbling barely out of the gate. 
I would be fine with Thunderbolt if it didn't prevent Apple from supporting USB3 right now. But of course, Apple's vision of purity can't allow an inferior port like USB 3 -- which is already very fast and already has good support from third-party peripherals *today* --  to take anything away from a new port that will probably have no credible peripheral community for at least two years. 
Who loses? Apple's customer, who hasn't gotten a high-speed port upgrade since FireWire 800's introduction in 2003! That's 8 bloody years. Apple skipped eSATA entirely, and now it's skipping USB 3 while Thunderbolt creeps along at a snail's pace, watered down by its exclusivity in Apple products, incompatible connectors, non-existent peripherals, and the fact that you can't add Thunderbolt support to existing desktop computers via add-in cards. 
Stupid, stupid, stupid.