Your decision will be based upon what you want to buy and what you wanna do. If you want a 650, then right now Verizon is out. If you wait for them to get it....if they get it....and data service is important to you, they have the fastest network but it's like $5 a month and only available in 21 cities.

If you want to travel internationally or use the same number for 2 or more phones, that' puts you in GSM AT&Tingular's (my name for the AT&T-Cingular merger) corner . They have broadband data service and geographical coverage is greater than anyone else's at about 55% of continental US. A lot of non coverage areas west of Mississippi but this covers areas where more thna 95% of people live.

Sprint doesn't have broadband data service but their data speed can approach that of Cingular on short transfers because of the latency which exists on Cingular's EDGE service. If you are doing a DUN connection to your laptop and sending bif files, then the broadband advantage reallly kicks in.

If it's basically a phone you want, the ebst thing is to check the siugnal in areas which you freqient as this should be your overriding factor above all others.

Out here on eastern Long Island, the only service I get inside and around my house is Cingular. To get a Verizon signal for the other phone in my car, I gotta drive about a mile. Right now I have personal / corporate phones for Verizon, AT&T and Cingular. In my area, I'd rate signal availability for:

Cingular at 95%
AT&T at 90% (MY Nokia AT&T's drop out in places where Cingular holds strong)
Sprint 85%
Nextel 70%

When I travel, "locals" tell me they do better with one or the other so it really depends on where you spend the most time. The exception tho is Nextel as I see many people with two phines on their belt, the Nextel for the walkie talkie stuff and half their calls and another for when the Nextel don't work.