I think this video best proves what I like to say about Jobs' presentations: it's not always that he's best of show, though he's had great moments. Very often it only seems so brilliant because he so often reveals monumental products.
Someone could give a one-off presentation that might wow you more than any single Jobs presentation. But I can't think of anybody in recent times who has delivered more total wow over the course of his lifespan.
It's also why he's such a good salesperson. He's got the best product. It's also how the Apple web site works: they have an almost pornographic display of their material. I love it. It sells better than any hype could.