Having worked on Windows Mobile for 3.5 years, mobile AIM clients for half a year, and now BREW for 9 months, I have to say that Apple nailed it with the 2.0 release. App Store is everything BREW ever was, but more elegant, easier to use, and I suspect their dev kit is way less irritating than Qualcomm's. The Exchange push mail support feels way faster and easier than Microsoft's own mobile OS - and of course the phone doesn't do dumb Windows Mobile things like beep (even when set to silent) when the battery is low. Finally, even the AIM client on the thing is way more stable and smooth than any one I ever worked on. It's a great piece of work.
Immense thanks are due to bikerbaer, ranger1, and all of the other Apple engineers who made this thing happen.
And yes, I still wish it had a decent camera, but hey. I need a reason to buy the LTE version whenever that comes out, right?