I was just looking closer at the interface today and noticed something which seems kinda odd to me. It is the presence of the 'Text Only' enabler in the 'Toolbar Customize...' settings, which seems kindof an unnecessary option. Have a look:
Removing the Text option to Customize Toolbar completely would be much more elegant i think. The Icons you use are very clear and pretty. You're also already making nice use of Mouseovers (Toolbar Tips?) to the buttons!
