Picasa versions

v3.9 [Mar 18, 2011]
1.Added ability to upload to Google : share with circles, post pictures to your stream, and upload images at original size.
2.Social Tagging: name tag people in your Google circles and notify them via G .
3.New photo editing effects, including:
Infrared;
Lomo-ish;
Holga-ish;
HDR-ish;
Cinemascope;
Orton-ish;
Sixties;
Invert Colors;
Heat Map;
Nightvision;
Cross Process;
Posterize;
Duo-Tone;
Boost;
Soften;
Vignette/Matte;
Pixelate/Focal Pixelate;
Focal Zoom;
Pencil Sketch;
Neon;
Comic Book;
Border;
Rounded Edges;
Drop Shadow;
Museum Matte;
Polaroid;
4.Side by side editing: compare two pictures side-by-side, or compare different edits on the same picture.
5.Updated RAW support for pictures from newer cameras.
6.Support for WebP files.
7.On the Tools > Experimental menu, we've added support for migrating your database to another local drive.
8.Improvements to Face Movie maker: number of photos included, chronological ordering.
9.Sync now uploads unshared albums privately.
10.Improved restoring of virtual albums when you uninstall and reinstall, or move to a new computer. Album data is written to the picasa.ini file now, along with all of your other edits.
11.OAuth support: use 2-factor accounts without getting an application-specific password.
12.Fixed various crashes.
13.Fixed name tags and contacts issues.

v3.8 [Aug 17, 2010]
Picasa has made it easier to organize your photos without opening your browser. Apply Picnik’s photo-editing awesomeness to your photo and save it back to Picasa. Then make a Face Movie out of your portraits. In this new version, you'll also find an amped up properties panel and a new Batch upload option so you can upload your entire photo collection.
Face Movie--You might be in charge of making a slideshow for a birthday party or wedding. Maybe you have only have two days and all you have is a bunch of group photos. Don’t panic. With the new Face Movie, you can quickly create a slideshow featuring that special someone, centered around that special someone, complete with transitions, music and captions.
Batch Upload -- Manage and organize your photos -- We've improved the the upload feature so that you can upload multiple albums to Picasa Web Albums at the same time. You can also remove albums, change upload size, visibility, or the sync state of photos that are already online on Picasa Web Albums.
Edit in Picnik -- Apply Picnik magic to your photo by selecting Edit in Picnik from the Basic Effects tab. Picnik is an easy and powerful photo-editor that allows you to edit photos easily, share them and save them back to Picasa Web Albums, right in your browser.

v3.6 [Dec 8, 2009]
Picasa 3.6 has improved name tags, a feature based on the same technology that powers name tags on Picasa Web Albums. With name tags, you can organize your photos based on what matters most: the people in them. In this new version, you can also upload photos to your friends' collaborative albums, more easily geotag photos using Google Maps, and import photos from your camera and upload them to Picasa Web Albums in one step. Get started by downloading Picasa at http://picasa.google.com
Add name tags -- Picasa scans all the photos in your collection, identifies the ones with faces, and groups photos with similar faces together. It's easy to add name tags to dozens of photos at once by clicking "Add a name" below a photo and typing the person's name. Once you've tagged some pictures, you can make a face collage with one click, easily find all your pictures with the same two people in them, or upload your name tags to Picasa Web Albums.
Collaborative albums -- Upload from Picasa -- In August 2009, we introduced collaborative albums in Picasa Web Albums. Now you can upload to a friend's album directly from the Picasa software.
Geotag your photos with Google Maps -- Quickly add geotags using the newly integrated Google Maps. Click the Places button and drag your photos to the location where you took them. Of course, you can still use Google Earth to tag or view photos if you prefer.
Import, upload, and share, all at once -- We've improved the import process so that you can star your favorites, upload to Picasa Web Albums, and share with Google contact groups at the same time.
Tags -- Better bulk tagging, quick tags & tag counts -- We've improved the tagging experience. Just click the new Tags button on the right side of the Photo tray to add Quick tags , see tag counts for groups of images, and manage tags more easily.