What do YOU want to know about UAC?

Well I was polishing my UAC session for Tech Ed this year. It occurred to me that there are bound to be a lot of actual questions about it.  So what I thought I'd do is ask you for your questions.

So tell me, what do you want to know about UAC? Post your questions here and I'll include them (or all that are applicable) in my session at Tech Ed. Just post replies to this post and we'll keep track of the ones you want answered.

Here's your chance to ask a question without having to raise your hand in front of everyone. :-)