Fedora 18 won't boot properly after yum update

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http://forums.fedoraforum.org – Version-Release number: Fedora 18 Beta (i386) running in VMWare Player 5.0.1 with a Windows 8 Pro (32-bit) host operating system. Description of problem: This morning (12-4-2012) at around 11:30 am PST, I ran a yum update command to update packages. The update completed successfully and I rebooted. After the reboot, Fedora boots as far as the desktop background before it stops. In other words, the desktop background displays, but the menu bar doesn't and I'm unable to do anything on the desktop. It won't even let me switch to a terminal. I didn't bother to keep track of which packages got up (HowTos)