I kept running the install, and no preference pane would appear. The logs didn't seem to indicate any thing wonky. OS X was copying over the Preferences Panel, but then deleted it when I started up the Preferences. So, before it could delete it, I copies it out of /Library/PreferencesPane into ~/Library/PreferencesPane/
And now it seems to be working well.
I'm excited to start using iCal as my only calendar again.