Here are some new UI-related tricks which you may find useful:
1. Docked Navigation Bar (View | Navigation Bar) now shows Run/Debug controls if the toolbar is switched off.
2. You may also switch off Tool Buttons (View | Tool Buttons) and get them to appear on demand by pressing Alt key twice (or Command key on Mac OS X).
3. If the new dark tooltips on Mac OS are too hard for your eyes, go to “IDE Settings | Appearance | Tooltip mode” and set it to “System”.
These new features are available since recent IntelliJ IDEA 10 EAP, so try them now and tell us what you think!