Who is the best presenter? Who is the worst presenter? Why?

So, you've watched a whole load of clips on presentations and of presentations.
Who would you say is the best presenter?

Ed Tate?
Randy Paunsch?
Doug Jeffrys?
Dick Hardt?
TJ Walker?
Or the Microsoft dude? (Should he even be on the list?)

Why?

What have you learnt from the video clips you've watched? Write your comments in your own blog. As agreed, your comments should be written in one or two paragraphs, min 100 words, max 250 words. (Due: Week 5)