The picklist currently has three types of events: source, taget, and global events. Global is perhaps a bad choice of words, but I mean events that apply to the picklist as a whole.

I'm wondering to waht degree this makes sense.  For instance consider focus, mouseover, and click events.  You can listen to one of these events for specifically the source and target lists, but you can also listen to the global event.  Is this overkill?  Would it be sufficient to have the source and target listeners?

If we did drop the global listeners, interactions with the buttons in the middle would be lost, but the impl would be much simpler.  Perhaps we could add button specific events instead?