Having come from Blackberry, though, I would advise running away as far and as fast as you can. In my experience (and the experience of most BB owners I personally know, though certainly not all BB owners), they are fussy, quirky, high-maintenance, and have severe limitations if you do not have them paired with a company's enterprise server (as I did not.) Add to that the increasingly common world-wide network outages, not to mention the also increasingly precarious viability of RIM (the company that creates them), and I really cannot recommend BB as a good option. That having been said, they do still have the largest selection of smartphones with a physical keyboard at this point, and I do know people who are willing to put up with the inconveniences just to have a keyboard.
I've noticed that this seems to be the case with certain BB models, but not all of them for some reason or another. My BB Torch is awesome. I have never had a problem with it, and I honestly would hesitate to ever trade it in. It does everything I need it to do, and it does it well.
However, I have known people with different BB phones, and they have had a variety of issues with them.