i see this as well. if you uninstall compiz-extra, the "flickering" stops, and everything returns to normal.
if you restart the computer with compiz-extra on and desktop effects enabled, the gui fails to load. -- Loading any Compiz-Extra plugins causes Compiz to segfault https://launchpad.net/bugs/97661 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
