"Welcome to the Adobe Photoshop Lightroom 2.1 release candidate on Adobe Labs. The ‘release candidate’ label indicates that this update is well tested but would benefit from additional community testing before it is distributed automatically to all of our customers. The Lightroom team would like the community to help verify the quality of this update through normal usage as this will ensure that the application is tested on a diversity of hardware and software configurations not available internally at Adobe."
You can download the update/release candidate here.