It's true that Jobs isn't necessarily the best presenter in the world. But I haven't seen anyone who can continually present their products with the purpose, passion, and pride that Jobs does, all of which are on display here. (No doubt because, as you say, 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.
Absolutely! I love Jobs. I've tried to watch every keynote he's given. He's magnificent. But I feel that if he was told to give a keynote about a worse product, he'd refuse outright. A part of his passion comes from his belief that his product is the absolute best.
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.
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.