I am having the exact same problem. I am seeing a lot of warnings similar to “Unknown property ‘border radius’. Declaration dropped.” in the Firefox error console. Also tried IE 8 and Chrome.
These errors seem to be related to the load-styles.php in wp-admin.
I should also note that I cannot use the ‘Add new category’ link in the post page either. Editing a picture’s properties by clicking on it no longer works as well. These may be related, but I am not sure.
