I was using Nokia since last 8 years and got a new blackberry this feb only and in my opinion blackberry is the best.
I have Nokia's E90, E61i, 9300i, N93,6630, Motorkr (motorola), W830 (Sony) and all these sucks comparitively to blackberry curve (I am proud to be a owner of blackberry
) and more then proud it allows me to not to carry multiple devices like mobile for e-mail and PDA for other stuffs.
Now waiting for RIM 9000 (or whatevery its name).....
And those who say it sucks either they are not a member of these two forums (flackberryforums and crackberry) or they are really dumb that they can't use it properly.