Eden
I took this picture while I was visiting the Eden Project and thought it might make a nice concept for a Fedora wall paper theme.
The bits I thought were most important to the theme were the roots extending below the ground, and the flowers appearing on the branches of the tree. If you want to get all deep and meaningful, I guess the roots could represent the solid base that Fedora is building on: the concepts of free software and open community; the flowering branches represent Fedora's rapid growth and all the new ideas that we're bringing into the world all the time :)
Could be a cool opportunity to do something that branches away from the traditional Fedora blue, using more earthy colours. We could always make the flowers blue too, which would help provide a nice link to the more traditional approach. Then again, I'm no artist!