TechLifeBlogged

Picasa, my favorite tool for managing photos, has had a huge upgrade. Highlighted in this release are:
Share photos online
Nested Folder View
Save Changes to Disk
Improved import
Screensaver
Geotagging
New RAW features
Other goodies
* Improved caption editing
* Starred photos organize automatically into a special album
* "Just raw frames" option lets you export time-lapse sequences in the movie maker
* The bottom row of buttons can now be configured to suit your needs

This is also Tools -> Experimental menu for some other things Google is trying out.
From Official Google Blog:

Folders finally work as you'd expect, so people who've kept their photos meticulously organized in folders and subfolders can see them displayed the same way in Picasa. And we've added a shiny new feature to photo-editing: Save. Your Picasa edits can now be preserved when using other programs. The save feature is even undoable, so you never lose your original files.
And there's more -- you can import into any folder you like, make time-lapse sequences into movies, search by color, create a screensaver with beautiful visual effects, and even re-arrange Picasa's buttons. Oh, and we also made Picasa work with Google Earth, so you can put information about where you went on vacation into the photos themselves, and then, view your shots on a 3-D globe. Try it all out for yourself at picasa.google.com.