I have been using Blackberries for many, many years and I think they are great devices. None of the ones I have owned have ever had a camera. I used to use the Cingular/AT&T network and over the past 2 years or so have been using the Sprint (which now own Nextel) network. The Sprint data network is the best I have used with their EVDO technology. Verizon uses the same technology so theirs should be the same speed, although I have heard issues with their definition of the term "Unlimited" as it relates to their data plan. They seem to have set some limit on how much data you can send/receive. Using applications like google maps, the web, email attachments, etc. on a Blackberry can consume some bandwidth. Sprint doesn't seem to have an internal definition of what "unlimited data" means. The coverage has also been much better than ATT/Cingular.
On the other side of the coin my wife just switched from a TMobile Sidekick to an iPhone. This is a completely different beast than a Blackberry, a really nice consumer device, decent phone, great voicemail, great ipod, great video, great internet, crappy keyboard until you get used to it. She really likes it and it has some wow factor. You cannot email while you drive as there are no "real" buttons. The network is much better than the TMobile network but AT&T Edge isn't nearly as fast as EVDO on Sprint. But when you are near WiFi you can use that and get way faster than any cell network. Very nice device which I am sure will get better with software updates.