If you upgraded to wordpress 3.3 you will notice a lot of plugins breaking that have a dashboard functionality. They are using the following code:

wp_admin_css( 'css/dashboard' )

Which stopped working in 3.3. It might happen in other plugins as well if they are using wp_admin_css. My advice would be to hold off on upgrading until they get this sorted out.  I don’t have time right now to do this myself.

Plugin Authors: If you are having a problem with your plugin, you can comment the wp_admin_css and do a wp_enqueue_style instead.