See the following page for the F15 Artwork Schedule: F15_Artwork/Schedule
Default Wallpaper Development
The winning concept selected by the Fedora Design team on January 18, 2011 is Nightingale by Emily Dirsh. Her concept statement is:
Inspired by the Emperor and the Nightingale. Juxtaposes the systems created by man, and those created by nature, thus a nod to the Gaia hypothesis.
Post-Alpha Wallpaper Refreshes
Post-Beta Wallpaper Refreshes
Splash Screens Development
GRUB & SysLinux
KDM & KSplash
note: These are usually done by someone from the KDE team (I believe jreznik usually makes them), but it would be nice to reference them here as well as they are part of the release graphics too!