I may be mistaken, but I believe you can still charge the 920 via micro USB. So the "you can't use it while you charge it" argument is pointless. Wireless charging may be gimmicky, but it's one I want. I've no end of trouble with jacks wearing out and not always making a proper connection, for example. And being able to put the phone into a car dock and have it sync to the stereo, turn on hands free and start to charge, all without spending the extra time to plug it in sounds very convenient.
In fact, that was one accessory I was sorry they didn't mention. The 920 needs a good car docking system.