I think a choice like this comes down to what your priorities are. If multimedia is your focus you won't do better than Nokia. I've had a bunch of Nokias over the years and loved them. 6682, N75, N95, E71, E51, E90, 5800.
As my focus changed from multimedia to messaging, I found I was constantly trying to coax my Nokias to do exactly what BlackBerrys are designed to do - email & PIM. Nothing in the world handles communication like a BlackBerry. Stone-cold reliability and messaging handling are two of the cornerstones upon which RIM built the BlackBerry empire.
BlackBerrys do have some multimedia capabilities. They can browse the web (fair to only decently), play music (no frills player, limited supported file types), and take pictures/video (like the browser, only fair to semi-decent). It's almost like RIM added these capabilities as an afterthought, as if to be able so say, "Yeah, we do that consumer stuff too." It's tough to beat the camera on the Nokia N95 even after the years it's been on the market. Music/video capabilities on the 5800 are stellar. What the Nokias all lack though is a world-class messaging app. BlackBerry has that.
I personally hated the Storm. I couldn't get used to that touchscreen for typing. Probably why, as a confirmed Mac Zealot (Maclot) I never had any interest in the iPhone. My priority is email, and typing 40-50 emails per day just wasn't do-able on the Storm for me. Other folks do ok on the virtual keypad. Not me. I need a physical set of keys, so I stick with the models with full QWERTY keypads. Previously that was a Bold (AT&T), now it's the Tour (Sprint). I'd love to demo the Storm 2 if it ever makes it to Sprint as I've heard the new model addresses a lot of the issues with the original Storm. So I'd like to try it, with skepticism and caution. That huge screen is a sexy selling point though, huh?
Bottom line is to honestly evaluate your usage patterns and priorities. What do you really
do with your mobile, on a day-to-day basis? Once you do that, the choice will probably make itself.