First Some Background...
Picture Switcher is a menu bar item that give you immediate access to your desktop pictures. With just two clicks you can change the picture displayed on the desktop by stepping through menus that show everything in your Pictures folder, as well as your iPhoto images and the built in Apple selection.
The menus don't have thumbnails so choosing a picture could be confusing unless it has a descriptive name, so there's also a built in browser.
Apart from being quicker than using the standard preferences pane, Picture Switcher also helps by being able to burrow down through sub-folders of the Pictures folder. There are also a few more options regarding the automatic changing of pictures—you can now have the picture change every time the Mac wakes, or every time you log on...