Peachpit Press is now shipping my latest book, Lightroom 3 Visual QuickStart Guide. A new blog/companion site can be found here with lots of info, including sample content, the table of contents, and lots of tips.
Lightroom 2.3 and Camera Raw 5.3 are now available for download.
In addition to added support for a few newer cameras (the Nikon D3X and Olympus E-30), there have been lots of little tweaks to Lightroom overall. Nothing major, but all signs of Adobe's continued dedication to keep Lightroom the best tool around for digital photographers. Adobe's installation PDF has the details.