Today's upgrade screwed up my places menu

Wed Dec 1 04:00:20 UTC 2010

Today's upgrade to Ubuntu 10.10 64 bit (Included Linux Kernel 2.6.35-23 
generic) went a little crazy on my machine.  Now, when I click on Home 
Folder, Desktop, Documents, etc. instead of a copy of Nautilus, I get
Appearance Preferences overlaid with an error message:

[item from Places menu] does not appear to be a valid theme.

For example: "Desktop" does not appear to be a valid theme.

Who needs to know about this?