The article from the first link is a little better explanation than the second link.
This is not quite a hologram, but it is a true multi-viewer solution without the need for headtracking or other dynamic tricks. It is a precomputed video stream displayed on precisely spaced, and slightly higher-than-your-living-room-tv-refresh-rate, but otherwise normal LCD panels.
Basically, the MIT guys have come up with algorithms to compute a set of three overlay transparencies, which selectively occlude or reveal certain pixels when viewed from certain angles due to parallax, such that one of many possible perspective images of a scene is produced depending on the angle from which this stack of overlays is viewed.
The part they seem most proud of is that because these different perspective views are all of the same scene, many of the pixels are the same color from one perspective to another, so they only need to concentrate their parallax trick on making a select few pixels vary by angle, thus reducing the complexity of the problem to the point where it can actually be realized with consumer resolution LCD panels and attainable data rates.