Same issue here, and I can't access the CP anymore,
You don't have permission to access / on this server.
[Mon Feb 25 17:52:16 2013] [error] [client 10.0.0.103] client denied by server configuration: /var/www/
the error message and the log of the error,
It worked like a charm before the update...
This is the only other thing i found related to this error message.