A blog post at The Lightroom Queen blog lists the changes in this release, particularly it's new video handling and tethering (which works with several Canon and Nikon DSLRs.):
- Videos can be tagged, rated, filtered, added to collections, saved in smart collections, and managed just like the rest of your photos.
- The little video camera icon identifies the videos and shows the length.
- Double clicking on the video, or clicking on the icon, will launch the video in your default video software.
- Video support does not include editing within LR – that’s not its job.
- Limited set of certified cameras to start with, but more will be added. The officially supported list is: Canon 1Ds Mk2*, 1D Mk3, 1Ds Mk3, 1D Mk4, 5D*, 5D Mark II, EOS 40D, 450D, 500D, EOS 7D, EOS 1000D, Nikon D3, D3X, D3s, D300, D300s, D5000, D700, D90. Other Canon cameras may also already work, other Nikon options are a bit more limited at the moment.
- You can view the camera settings but you can’t change them remotely.