With the qualifier of being a user interface tool, which is in the same sense Steve Jobs meant it in the first place rather than in the "hey look, a stylus, the stylus isn't dead" context that everyone else was using in this thread.
I didn't get that impression, I think most on here agree that the stylus shouldn't drive the interface, it seems that there really isn't a discussion so much as a lack of understanding. Whether it's what Jobs meant or not who knows.
My personal opinion is IF he did include a stylus in the first iPhone it would have been a hit and indispensable and instead of discussing this we'd be discussing how Samsung stole the stylus idea away from Apple. We might have had some serious innovation, maybe even the end of paper as we know it. Kind of like facetime or SMS maybe note taking would have become as ubiquitous as using a piece of paper and a real pen. Sharing and collaboration, syncing between multiple devices, searchability, etc.