I left AT&T the day Verizon got the iPhone and swore I would never go back. Lousy coverage and lots of dropped calls. Maybe they are better now but I don't really want to take a chance.
Verizon has much better overall coverage especially outside of major cities on highways and smaller towns which is important to me since I travel for work a lot and also do a lot of long distance bicycle events which are usually in more rural areas.
It's almost like they are trying to sabotage the HTC One by making people wait to along and introducing the S4, new Droid phones, and maybe even the Moto X first.
Carriers choose phones for many reasons like how much the phone costs them, how much bloatware can they put on it for additional revenues, warranty coverage and availability of new and replacement phones. I'm getting the feeling Verizon would not be getting the HTC One at all if it weren't for customer complaints. But they sure are rolling out everything new before the HTC One. They could have had it at the same time or before the S4. Maybe they don't consider HTC a good partner for some reason or reasons I dunno.