Yeah...BBF is the wrong place to expect anything but a pro-BlackBerry vote.
But, having had a long relationship with Treos before coming to BlackBerry...I can still say that, although I really did like my Treo 680...I really do prefer the BlackBerry in almost every single area. I was actually one of the few Treo owners that never had a single problem with my 680 being buggy or acting weird...but, I got tired of the bulkiness of the phone itself, the "plain" display, the difficulty using it one-handed, the build-quality...and the open-platform that allows for many Treo-modified apps that can and will sabotage the phones reliability and make it buggy and quirky. The "closed"-platform of the BlackBerry that will only accept made-for-BlackBerry apps, keep the BB safe and sound...and although I have quite a few 3rd-party apps on my 8310...it still runs as fast as it did when it was "clean" and never misses a beat or freezes. It remains stone-cold reliable...a BlackBerry trait.
I must admit that I prefered the qwerty keyboard of the Treo over that of my Curve...but that is personal preference, and many would disagree. The Curve's keypad layout is great, but the Treo has it's keys just spaced a little farther apart and the shape of each key is just more condusive to typing quickly and error-free.
Overall though...the BlackBerry is the clear winner. I would never go back to the Treo. In fact, having had pretty much every smartphone to come down the pike in the last few years (many much more expensive than either the Treo or Curve) I can honestly say that I am not even considering another device other than BlackBerry at all now. That's a pretty big statement from a confirmed "phone junkie" like me!