What makes a good keynote speaker good?

David Jakes is going to be a keynote speaker at TechForum Chicago, and on his blog he asks this question: "When you attend a conference, and attend the keynote, what kind of presentation are you looking for? Do you look for more philosophical, or practical or a mix of both? What attributes does a good keynote have?" He invites your comments and suggestions on his blog. Here are mine, in no particular order.

I appreciate a keynote speaker who sounds prepared--polished, but not perfect--and doesn't sound like he or she is reading from a teleprompter. I've been to a few keynotes where the speaker sounded like he (yes they were all male) was winging it. Just kind of wandered from one point to the next with no clear direction or point to what he was saying.

I also like hearing "the big thinkers" who challenge me to think different (isn't that an Apple promo?)

And speaking of promos, I don't like listening to keynotes that turn into commercials for a book, or software, or hardware, or whatever it is they happen to be selling.

I like speakers who tell moving stories will excellent visuals, not speakers who read their PowerPoint slides to me.

And I definitely appreciate a good sense of humor.

I want to leave the session with a feeling of hope, not a sense of gloom and doom.

Have I missed anything? Add your suggestions to David's blog: http://jakespeak.blogspot.com/2007/04/keynote-address-techforum-chicago.html