Ubuntu 11.04 has come out for few days, if you choose to upgrade from a previous Ubuntu edition you may encounter no wallpaper displaying problem in Unity. There’s only a white background and wallpaper chosen in Appearance window won’t display any more.
To fix the problem there’re two solutions:
Option 1: Run “gconf-editor'(without quotes) command in Alt+F2 pop-up window or terminal, then navigate to app/nautilus/preferences, un-check “show_desktop” in right.
Then wallpaper chosen in Appearance will be shown as background, but desktop shortcut icons and right-click desktop menus disappear.
Option 2: Install nautilus elementary and use Windows-like slides can perfectly fix this problem.
Install nautilus elementary from PPA:
sudo add-apt-repository ppa:am-monkeyd/nautilus-elementary-ppa sudo apt-get update sodu apt-get dist-upgrade nautilus -q
Check on Chinese Ubuntu forum