Jon Udell goes through the ways he prepares to speak; I know this drill pretty well. I've never actually prepared a talk in advance (as in, had a prepared text). Maybe it would be a good idea; I don't know. I've always used what he calls "mode two", a set of slides to remind me about what I wanted to say. I tend to do a lot of ad-hoc demos though, so I "wander off the reservation" a lot.

I have no real idea how effective I am at this; I've been getting in front of groups for years, so I assume I'm not horrible. It would be nice to get some feedback from people who have attended one of my talks though.