I've had a Treo 650 on Verizon for almost 4 months now. Everything you say is true, but there are a couple of other points:
1) I find that if I am in a location where the Verizon connectivity is "iffy" and the Treo spends time search for a Network it uses up a lot of power.
2) When you get an incoming call, after the call is over, if the number is not in your contacts you are asked if you want to add it. If you tap on "Yes" it takes you to the contact screen where you can fill in additional information.
All in all a great device.