I recently upgraded from 12.04 to 12.10. After logging on, I found that all of my items from 12.04 were still there, but the Launcher and the top bar were gone. Application top bars were also missing. After doing a fresh install, I still have these problems. I'm convinced that it's a problem with my graphics card.
Dell Dimension 3000
Intel Pentinum 4 Processor
Radeon 9200 PRO (According to the Windows ATI Catalyst Control Center, I have two of these)
Ubuntu 12.10 (Fresh Install )
Windows XP Professional (just in case WINE won't load an app)