When John Carmack, Gabe Newell, and the former designer formerly known as CliffyB endorse something, it holds more clout than your typical Kickstarter project.
The Oculus Rift is a set of VR-style glasses which enclose two screens with one for each eye. You are able to track head movement to look around. You are able to see in 3D without a loss of contrast or vibrancy or otherwise introduce visual artifacts — provided it lives up to the hype and testimony.
The Oculus was originally expected to ship at some point in December although backers just received contact by email (I have been unable to find a linkable source as of publishing) that first shipments will be available in March.
Apparently the original 5.6” LCD displays that were used for the prototypes have been discontinued by their manufacturer. The new display performs better than the original but adds an extra 30 grams of weight.
Oculus also decided to design their own VR sensors to track head motion. The new sensor polls 1000 times per second and adds a magnetometer, likely to be utilized as a compass, alongside the accelerometer and gyroscope found on the original prototype. I am not too certain how that will affect much of the core functionality but should allow for some interesting side projects.
If you held out through the duration of the Kickstarter funding period, the Oculus is available for pre-order with those units expected to ship in April.