I think the stroke of genius in the iPhone (and I fully admit this is obvious 3 years later), is that people want to do a wide variety of simple things on their phone.
If you are sending tons of emails from your phone, then yeah, the physical keyboard blows the onscreen one out of the water. But when you are running a dozen apps with completely different functionality, but all of them are fairly simplistic, a touch-screen (especially a good one) does a better job on average, as compared to a keyboard where you quickly descend into the buttons being meaningless ala Nokia endless 2-button menu navigation.
Now obviously you can have both (I bought a G1 back in '08 and I like having both), but it took balls for Apple to make that decision and say that a touchscreen only would be sufficient. However the impact of that decision on the elegance of the form factor is undeniable, and something that I imagine had a large if unmeasurable impact on the success of the iPhone. It's the type of thing that you need a product visionary at the top to achieve, otherwise it's DOA at the first board meeting.
If you are sending tons of emails from your phone, then yeah, the physical keyboard blows the onscreen one out of the water. But when you are running a dozen apps with completely different functionality, but all of them are fairly simplistic, a touch-screen (especially a good one) does a better job on average, as compared to a keyboard where you quickly descend into the buttons being meaningless ala Nokia endless 2-button menu navigation.
Now obviously you can have both (I bought a G1 back in '08 and I like having both), but it took balls for Apple to make that decision and say that a touchscreen only would be sufficient. However the impact of that decision on the elegance of the form factor is undeniable, and something that I imagine had a large if unmeasurable impact on the success of the iPhone. It's the type of thing that you need a product visionary at the top to achieve, otherwise it's DOA at the first board meeting.