Adobe has just released Adobe Lightroom Beta 3, their RAW image processing solution currently only for Mac OS X. Download and try this public beta release at the above link.
For extensive coverage of the functions in this release, read photoshopnews.com’s article on Lightroom Beta 3.
Edit: I just had a quick look at the program and I personally find that it’s still far too slow for my purposes. I’m running a 1.5 GHz Powerbook with 1.5 GB RAM, so I am above the system requirements, but operations that happen quickly in Adobe Camera RAW just take too long with Lightroom. I hope that the program speeds up in future releases because a number of the features are attractive and it could be a good addition to my workflow.