Lightroom 3.4 RC
Adobe have announced a Release Candidate for Lightroom 3.4 and Camera Raw 6.4. Mostly bug fixes with new camera lens profile support. Full list here.
A Release Candidate means it is still not a final product and not (yet) supported. But if you have a new camera and/or lens and want to use Lightroom it is safe to try. Download Lightroom 3.4 RC here.