I think I’ve found a temporary (if inelegant) fix for the problem of WordPress not showing up.

Go to your blog (or where your blog should be) and add “/wp-admin/” at the end of the url. So, you’ll have an address like this:

http://www.domain.com/wordpress/wp-admin/

You should see the login screen. Log in, go to the “presentation” tab. Select the “WordPress Classic” theme as your active theme. This seems to bring back most of the blogs.