I just returned to Verizon after hiatus while being on my new wife's AT&T plan. We moved to FL for her to do a Disney internship, and the other service completely sucked.
I got the Vortex because it wasn't terribly expensive, and is much like the iPhone 3G I just had. I like the flow of the screens, the icons, and the general feel of the apps and user screens. It will take some getting used to the virtual keyboard differences between portrait and landscape modes.
I'm off to extend my Vortex usability knowledge.