Does Android's turn by turn include the maps, or are they downloaded as you use it (basically you need internet connection to use it)? Cause personally I want my phone to function as a GPS independant of internet access (There have been times before I bought Navigon that I wanted to use the GPS and could not because we were out of any coverage area).
Personally, I'll take the iphone without turn by turn and just buy an app *that includes the maps* (like Navigon or TomTom) than pick android just cause it came with turn by turn.
Especially since, honestly, you can find free turn by turn on the iphone if you don't mind not having the maps (mapquest makes an app for that that's free). So really the only real difference is one you have to actually download the app, the other one already comes with one. But since you can have the same thing, just requires you look a little, I'll pick the one I like best for other reasons other than turn by turn. Cause you aren't missing it at all if you get the iphone long as you are willing to search for a navigation app.
So, honestly, I don't even understand the argument that you should pick android cause it comes with turn by turn. So what? You can get that free for the iPhone too.