SAN FRANCISCO -- There have been many, many keynote performances by Steve Jobs over the years at the various Macworlds and at WWDC. Some have been disappointing. Some have been very good. Some have had long winded iLife demos and various bloopers of some kind. I have been present for dozens.

In a recent keynote, several other Apple employees, Scott Forstall and Bertrand Serlet, joined Mr. Jobs on stage, but it seemed to detract rather than add to the presentation. In this keynote, aside from three other CEO partners, Mr. Jobs did it all.

Mr. Jobs gave the solo performance of his life. He was obviously feeling great. He was composed, articulate and passionate.

He spoke firmly and flawlessly about the iPhone, clearly a product that he felt, and weill all come to agree, will be another seminal product from Apple. The iPhone is everything we hoped it would be and more.

There was only one small snafu, when his clicker failed, and Mr. Jobs used the occasion to gracefully tell a humorous story from earlier days while the problem was fixed.

In my last Hidden Dimensions column, I remarked that this would be a very important keynote presentation with enormous stakes. In fact, Mr. Jobs exceeded our already stratospheric expectations, and that is a remarkable achievement. At the end of the keynote, Mr. Jobs paused for a few seconds, apparently overwhelmed by the poignancy of the moment and waxed philosophical about why Apple does the things it does.

It was perfect.

The iPod changed everything. And now the iPhone will too. The world will never be the same again. Thank you, Mr. Jobs. And everyone at Apple, Inc.