See the word "BETA" on the top, right?
Lightroom 2 Beta
Today (April 2) Adobe released the beta for version 2 of their Lightroom product. They will collect user feedback and make further adjustments until the official version 2 release date in August.
(I suspect Adobe wanted to get something out now because Apple already released version 2 [and 2.1] of their equivalent product, Aperture.)
The most publicized feature is the ability to make adjustments to a single area within the image -- adjustments in Lightroom 1 were always applied to the image as a whole.