If you don't type a lot and are a more casual user, the availability of apps for the iPhone is cool, and the interface is very elegant.
But it doesn't multitask, which can be very frustrating for anything beyond casual use. Also, currently, you are stuck on AT&T with the iPhone. AT&T's service is really bad in many places, and the network, esp the data network seems overcrowded so hence, doesn't perform well.
If you really need to get actual work done, get a BB with a keyboard. If it were my choice, I'd get it on a network other than AT&T. I like Verizon.
To put it more simply, the iPhone is cool, sexy and sort of fun.
The Blackberry is less sexy but really good at just getting things done.
My smartphone isn't a casual toy, so I'm Blackberry all the way.
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