I read a great post over at Ajax Performance defending AJAX as the iPhone development environment. This reminded me of my own take during the iPhone brouhaha, and I decided I had a little more to say.
Web development is has come a long way, but building a local app still has a lot of advantages. But, hey, when the first cars came out, horses were still a lot better. Apple didn't decide on AJAX because you can build cooler apps - they decided on it because it is the future, it is where the talent goes, and because . Google has managed to become the most valuable brand in the world without an OS and a native API.
Apple is obviously committed to this - they were willing to not bothering with an native API. Time spent with a Cocoa iPhone is time not spent making the web better.