As for the Blackberry, my brother has the Blackberry 8830 (the top-tier one) and I've played around with it a bit and I think the iPhone is something I would get more use out of. Blackberry is more business oriented and a lot of the features it has I'd never use. iPhone seems to have more of the fun stuff.
What sort of things are you referring to? I have a Pearl and it does POP3 e-mail (in addition to the normal BES link to an Exchange or Groupwise server for business customers), Internet, and has a phone, camera, media player (albeit a crappy one), and it supports installed apps. I have Google Talk, a Facebook app, Google maps, Opera Mini, and several games. There's no question that the iPhone interface is the slickest around, but what "fun stuff" does it have that you can't get elsewhere?
I'm not trying to start a Blackberry vs. iPhone debate but I'm just curious to see what people are looking for.
I looked at the iPhone when Jennie was getting a new phone at the AT&T store the other day. I liked the interface, albeit it was a bit daunting to navigate as a rookie user. What I don't like is the size. It is way bigger than I want out of a cell phone. I thought about getting a Curve for my next phone, but even that I think is too big, and it's smaller than an iPhone. I'll probably get another Pearl, but with wi-fi.