Ostensibly we can assume Microsoft will eventually release a commercial SDK with a full license to market applications developed for their cool little toy-thing. Can you say Minority Report windows interface? I can. One of the reasons I actually bought a Kinect in the first place was for that very reason. Well, that and an awesome Star Wars lightsaber combat game, but of course we've seen what happened with that little dream of mine.
The SDK includes official drivers for using the Kinect on Windows 7 machines, API's and device interfaces for working with the hardware, samples of source code for people to get their bearings, and technical documentation, too. Get ready to see significantly more Kinect apps being released in coming weeks and months.