UPDATE 2: June 16, 2011
The Kinect SDK (beta) has been released on June 16, 2011. Download it here.
UPDATE: April 15, 2011
Scott Guthrie announced the SDK in his keynote speech at MIX 2011. Additionally, each attendee was also given a Kinect to start building new software with it.
For their annual April fools joke, Google introduced Gmail Motion in 2011. You can read more about it here: http://mail.google.com/mail/help/motion.html
Some laughed, others saw it as a call to action. A research team at USC (University of Southern California) called Google on their bluff and used their experimental FAAST engine to actually implement the functionality from Gmail Motion. Even better, Microsoft has announced that they are releasing the Xbox 360 Kinect SDK later this spring (2011). I have some ideas for this and will be writing about this separately.