The affects ALL themes.
No matter which theme I try to activate on a new blog that I have just set up, the theme does not change.
The themes page says that the current theme is the theme that I have selected, but the front end of the site still displays the 2012 theme. (which I actually disabled and made availale to NONE before creating the account because I don't like it).
So I cannot change the theme, and even though the 2012 theme is not active, new blogs seem to start with this theme anyway?
I have tried visiting the site in 3 different browsers, so cannot see how this is a caching problem, I have also cleared the cache at wordpress.