I don’t know for how long, but it seems picasa (2.2 and 2.7 beta) is available for linux.
What is Picasa for Linux?
Google’s photo organizer, Picasa, makes it easy to find, edit, and share digital photos on your computer. Now you can harness the power of Picasa on your Linux machine. Our Linux release includes the same functionality as Picasa for Windows with the exception of just a few items. (Please see our FAQ for more details.)
So, how does it work? Picasa for Linux runs the current Windows version of Picasa using a carefully tested version of Wine, an open-source implementation of the Windows application-programming interface (API). Wine runs on top of the X Window System and Linux or Unix. But it’s not a Windows emulator; instead, it provides a Windows API middleware layer that enables Windows programs to run on Linux without the slowing effects of OS emulation or a virtual machine.
To allow Picasa to run well on Linux, Google made a few improvements to Wine. Some of the changes were Picasa-specific and simply added a bit of polish. (They probably won’t be of use to other applications, and may not be needed in future versions of Picasa, either.) None of the changes were proprietary to Google, and all have been contributed to the Wine project. The source for all the changes is available at http://code.google.com/wine.html.
The .deb installer can be downloaded on this page (together with the .rpm).
The icon you see on awn isn’t the original, it’s from deviant art and can be downloaded here.