I noticed it too, requests are very long in postgresql and it triggers write-locks for update on tables at each run.
I and it's not a matter of upgrading a first time.
If I wait long enough, my page shows up and I can try a new request, but then it starts again updating.
but if I don't wait, I have the same message as yours.
It occurs since the merge of "list privacy" update with postgresql 9.1.9 from deb7 system
Hope this report helps
regards