There are several versions of Launcher.exe. Some are spyware. Go here
and type in the name, launcher.exe, and you'll see several things that use that filename.
Since Webshots used to include spyware, I have avoided them, though it seems they may have cleaned up their act. On the other hand, they can apparently slow down a computer considerably. See here
Personally, I'd rather simply change my backgrounds on a regular basis, picking what I want to look at rather than having it done for me, but to each his own. :-)