Picasa is not only a great web-based service from Google, it is also an excellent image management tool on the desktop. Using the Wine project technology, Picasa can work on Linux, although the Linux version is not updated as often as the Windows or Mac version.
There are pros and cons of the Linux version. It integrates more than merely running Picasa in Wine, but users still feel that Picasa is not a "native" application of Linux.
Picasa covers everything from basic editing to creating albums to changing your desktop wallpaper, which of course includes uploading images to Google's Picasa storage service.