Used a few Android phones and switched to an iphone. First of all, the main reason I switched to iphone is because I listen to lots of podcasts and the experience is much better on iphone. You can just go right to the itunes store from the phone and download them. On android, I have to use a program like google listen, which is in beta still, and not that great, and put the rss feed in and get them that way. Of course then, I'm limited to the rss feeds that I already have whereas with iphone all of the different categories and shows are right there and I can add new ones easily.
With that being said, the main things I like better about android-
1. more choice in devices (bigger screens, more power processors, etc)
2. voice input on keyboard, and alternate keyboards like swype
3. integrated google navigation
4. no need to use itunes
5. notification bar system
6. more free ad supported apps
my things I like better about iOS-
1. the aforementioned podcast scenario
2. kickass ipod built in/cover flow/ podcast ease of use, organization
3. buttery smooth performance despite lesser hardware specs
4. retina display on iphone 4 is really nice
That is just a quick summary of my favorite features, I don't have time to go into the cons of each so I'll just point out what is better in each of them for now.