OK, one feature that is really needed, in particular if you are doing toolbars, is support for the combined button/menu thing. For example, in MS Outlook there is a Send/Receive button. When you click it, it works as a button, but if you click the down arrow on the right (I'd like to be able to choose the left), it is a menu. We can do this now, of course, only that the two down hover together, and have that UI that people know means that they are together.

http://www.ozonline.com.au/image/windows/outlook/toolbar/sendreceive.gif