Mike Swanson,a MS employee has created a theme pack for Windows 7.Here is what his blog post reads-
Windows 7 introduces theme packs, which are .cab files that contain all of the necessary assets to implement a theme, including sound files and images. You can find a bunch of theme packs on the Windows 7 site, and Paul Thurrott covers the basics and includes his own theme packs in his article, Windows 7 Feature Focus: Styles and Desktop Slide Shows.
As an experiment, I’ve created a theme pack based on my wallpaper images. It contains 20 hand-picked, nature-themed macro photos that I’ve taken over the years. The desktop images are configured to shuffle randomly every 30 minutes. Otherwise, the theme uses the default Windows 7 color and sound schemes.
You can download the Mike Swanson Macros Theme Pack for Windows 7 (8.59MB)
thanks ya..