Adobe has made release candidates of Lightroom 2.6 and Camera Raw 5.6 available for download in Adobe Labs. These versions add raw file support for the following cameras:
Canon EOS 7D
Canon PowerShot G11
Canon PowerShot S90
Leaf Aptus II 5
Mamiya DM22, DM28, DM33, DM56, M18, M22, M31
Nikon D3s
Olympus E-P2
Pentax K-x
Panasonic FZ38
Sigma DP1s
Sony A500
Sony A550
Sony A850
Remember, these are release candidates, which means they’ve been pretty well tested and Adobe thinks they are ready for full release; however, it’s recommended that you keep production work to prior versions until the official releases drop. Expect those to come soon though. Release candidates mean that the final versions are just around the corner.
Lightroom 2.6 release candidate can be downloaded here.
Camera Raw 5.6 release candidate can be downloaded here.
Lightroom 3 Beta has not been updated yet.