Mmm.. I had a Blackberry once. The only thing I really liked about it was the speed and precision with which I could type on the physical keyboard. I still miss that from time to time, though the touch keyboards on my Lumia 920 and Nexus 7 are both excellent and compared with the Blackberry, I can type on them with about 90% the speed and 70% the accuracy (or vice versa).
The mail client was pretty robust from what I remember. BBM was useless to me because almost no one else I knew had a Blackberry. The only other thing that made a real impression on me was their app store, Blackberry World or whatever.. Not for anything positive though, but because of how atrociously bad most of the apps were. Many were absurdly priced compared to any other device and most of them were underwhelming at best and buggy and crash-prone or riddled with permissions issues. I found all of the developers I tried to contact for support really wanted nothing tho do with me and seemed to regret ever making a Blackberry app in the first place.
It was a great idea initially, but I get the sense that by the time I got there, about three years ago. I was stepping among the ruins of a crumbling, but once proud empire.
I know Blackberry fans are pretty passionate about the brand, though I'm sure their ranks must have dwindled by now. I'm curious to see if they can still save the Blackberry with BB10. From what I've seen it looks pretty impressive. Windows Phone is my phone OS of choice though (and Android for tablets) but I'll be paying attention to them this year. If nothing else, I think the competition will benefit all of us because it will ensure that no one rests on their laurels too much, especially Microsoft, who has the most to lose from a Blackberry resurgence.