Picasa Wined for Linux
Google ported, if it could be the word, Picasa to Linux using Wine. Picasa for Linux is available at Google Labs. Sadly the link doesn't seem to work from outside the U.S (at least I got a 404). Therefore, here is a direct download link for the Debian/Ubuntu .deb file. Don't worry if you don't have Wine installed since is comes with built-in Wine libraries. Check out the review over at Linux Help. Here is from the WineHQ Mailing List about Picasa for Linux.
From the screenshots it looks wonderful. Despite being a Wine-ed application, it doesn't really look out of place on Linux. On the contrary It looks beautiful. Maybe because it uses its own interface style and not the stock Windows widgets.