Google released a new version for Google Desktop (Google Desktop 4.0 Beta) that includes many interesting new features and has a slicker look.
Google Desktop can finally automatically remove deleted files from the index. You can add modules from Personalized Homepage to the desktop.
Plugins are now called gadgets and have a new development model - they are interactive XML mini-applications. Google Desktop will recommend new gadgets and can also automatically create a personalized Google homepage.
The gadgets are extremely well made: you'll find a media player with visualization effects*, Digg's top stories, del.icio.us bookmarks, a network monitoring tool (Desktop Netstat), a gadget that shuts down your computer on schedule, a disk fragmentation monitor, a tool for shredding files, a wireless signal meter and a weather 3D globe. Some gadgets (like ToDo list) can save the data on Google servers so you can access it from any computer.
Unfortunately, the RAM usage will be high if you choose too many gadgets.
* In case you were wondering about the Google Media Player, it's just a small skin for Windows Media Player integrated with Google Desktop. Try this: play a song with Google Media Player and then open Windows Media Player. You'll see the same song playing.