I have been waiting for a long time for this one! Download it here. Here is the Picasa team’s write-up over at Google Photos Blog. Here is the Techrunch review. Thanks @steverubel.
[youtube=http://www.youtube.com/watch?v=NDKFjc3_wrk&eurl=http://googlephotos.blogspot.com/2009/01/announcing-picasa-for-mac.html&feature=player_embedded]
