For those that may be a recent Linux convert from Windows, Google does support their Picasa software on Linux with a generic binary as well as separate packages for RPM distributions (Red Hat, Fedora, Mandriva) and Debian distributions (Debian, Ubuntu). Unlike gThumb and F-Spot, Picasa is closed-source software. The latest Picasa Linux release is the v2.7 Beta.
Picasa for Linux is extremely end-user friendly with a very well designed user interface. Picasa allows you to distribute photos by uploading them to your Picasa Photo Web Album, emails, printing, ordering professional prints, using Google's Blogger service to blog about a photograph, creating a collage, or exporting the photographs.
Google's Picasa also supports cropping, straightening, red-eye reduction, a "one click lighting and color fix", auto contrast, auto color, and various photo effects. In addition, Picasa supports batch editing of photographs.