While not completely impartial - I can tell you that if multi-media is of prime importance to you for owning a smartphone then go iPhone.
If smartphone functionality is what your after with the emphasis on phone, then Blackberry is the answer.
My reason for staying with BB
- Bluetooth headset voice dialing
- keyboard is much faster - I email a lot
- copy and past (seriously)
- BES server functionality
The flame goes on..
Blackberry since 2004, Torch currently