This is the same Steve Jobs who said there would never be an iPod that did video about a year before they did so.

They may have had the app store model planned out from the start for the next version of the iPhone, but didn't want to talk about it when releasing the first version because that would highlight the shortcomings of the existing product and cut into sales. But you still have to have an answer to the question of how you make software for the new product, so they say build web apps.