If you haven't changed anything, you didn't do anything wrong. There have been a few gremlins runnin around on the host server that is causing problems. One of them is as BD mentioned is the Snowman issue that people have been commenting on.
Methinks ... there are some spurious emmanations in the ether world
that is causing some weird stuff to happen
Hang in there, Dennis is aware and working on it.
Also, you might want to run a scan of your Anti-Virus and your Anti-Spyware suites... just to be on the safe side. I did yesterday after too many outages.. I thought maybe I had picked up a few bugaboos.. so I ran it just to be sure..
Found a couple things, but nothing that would change my thoughts on this.. it is most likely server related..