Lightroom 2.1 has been released after some week of a 2.1 Release Candidate version. Also Adobe Camera Raw for Photoshop has been updated.
This update just adds support for some new cameras and fixes a lot of stability and performance bugs.
Lightroom 2.0 infact was launched with quite a lot of problems for some type of hardware (like for PC with some type of graphic cards as well for Vista 64 bits).
After many complaints in the Adobe forum, Adobe listened to them and try to correct v2 with this update. First tests seem to show that a lot of items have been effectively fixed/improved.
We then wait for some functional update to Lightroom in the next update.