I carry a Blackberry Storm. It's the only phone that Verizon offers that has the GPS unlocked. Keep that in mind. Mines just for internet access and phone and SMS. I run a Garmin 305 with HR/Cadence for the rest of the stats.

Other than that, I'd say iPhone, but 12 other people in my department have them and all complain about battery life and ATT's internet service speeds/availability. There are some cool cycling/route racking apps for them though.