I hate both Verizon and AT&T. I just hate AT&T slightly less, and I really like the freedom in hardware that GSM gives you.
I also get a discount with AT&T through my work, but honestly I'd still choose them over Verizon regardless.
AT&T also gives me better reception around here, but that's because they took over the Unicel towers and Unicel (being a local company who could focus their resources in New England) kicked Verizon's butt in tower coverage. Your mileage may vary there though.