I finally made the switch from my Treo to the Blackberry. For the past 2.5 years I've been using the Treo and I feel like I just got out of an abusive relationship. The Treo Personal Business Connect Service was consistently UNRELIABLE. I was never 100% certain that the service worked. The VersaMail service, in theory, seemed great, but it was always terrible for me. As a phone it was fine, but that's not the reason I was using it.
So I switched to the Blackberry. I feel like a new person. It's reliable, was incredibly easy to set-up and did I mention it works???
Next change...making the switch from a PC to a Mac.