Blackberry Curve 8900.....would not go back now and most of my bberry friends are considering to follow but waiting to see what Torch is like....'whatsapp' has made it a lot easier from a cross platform messaging point of view! Love the quality, screen, camera quality, apps etc.,....miss being able to forward an sms from time to time....but am a convert!!
Went through a couple Blackberrys (Pearl, Storm1, & Storm2) and have an Android tablet before going iPhone4. iPhone4 is the most stable, intuitive, smoothest, & refined. As I always say, "It just simply works!" This is part of the reason that it has set the standard.
I had the Sprint HTC Hero. Ended up buying my cousins 3G back in December. I paid a 100 dollar early termination fee to get out of my Sprint contract. I got the 3G activated off contract with AT&T. Then I heard about the Radio Shack trade in special a week later and traded in the 3G for the i4.