I have the exact same problem, it seems. But mine started about an hour BEFORE I updated to 3.3. It occurred suddenly while editing, and I was hoping the upgrade makes the problem go away. No such luck. It afeects old and new posts, i.e. all posts get an empty editing window with none of the editing features working. I cannot even type readable text, i.e. the cursor moves but nothing shows. Picture upload does not respond, etc.
However, when using view post, the web site looks ok. Posts just cannot be changed, new posts cannot be created.
It seems that some other functions are disabled too, not just post editing.
I am usually running IE9 on Win 7-64, but it does not work on Firefox 8 or Chrome either.
Very strange.
Harald