Wow. Testy thread!
I have looked at most of the smartphones. I use an 8330 because that's what I can get on my carrier reasonably - despite the fact that it is late 2009, there are places where I can't get signal from anyone but Alltel/Verizon. I know. Poor me.
Anyway, the only reasonable answer to your question is to see if you can't get your hands on a unit and try it. iPhones are cool, so are Pres. I kind of wish I had a Pre since it's my understanding they can run old Palm apps, and compared to Palm there is a huge lack of math apps for BB like high level calculators, which I use daily (I am an engineer, and use solvers on a daily basis). At the moment I carry my BB AND a Palm Tungsten IIe, and I wish I could just carry one or the other.
Now, if the iPhone had apps available like that, AND handled email like the BB, AND I could get it on my carrier so I could, you know, use it as a phone, I'd be all over it.