Manager Displaying as Text

I installed 2.1, put my site in, everything was fine. A week later I come back to add in more stuff, log into the manager, and this comes up: http://i.imgur.com/GolGy.jpg

Any idea what's going on? I haven't the foggiest idea what to check.

Obligatory bump because I'm seriously at a loss to why the manager is showing as plain text and I can't do anything.

It looks like the Manager CSS and/or JS is not being found. Do a "view source" on the manager page and look at the CSS and JS files included near the top. You can see the path where they are supposed to be and check to see if they are there. The permissions on those files or their folders could also be an issue.

It's worth asking your host if anything has changed. If the host turned on suPHP or suExec, the permissions should be 755 for directories and 644 for files.