I'm the exact opposite. I switched to FIOS because they had the same HD lineup as DirecTV at the time, if not slightly better (FIOS had all HD locals from two markets; DirecTV only offered four from Baltimore) and offered a far better HD picture. I actually ended up with a "quadruple play" package because I already had Verizon landline and wireless phone services. The real clincher was being able to dump Comcast wideband internet for the superior FIOS service.
DirecTV lept out in front of FIOS with the latest HD mpeg4 lineup but Verizon just activated a bunch more HD channels in my area as of yesterday and have promised more than 100 available HD channels by year's end. Based on my current viewing habits, there is only one channel left out of all the ones I watch on a regular basis that has not been made available in HD (Fx). I'm hoping that's one of the channels that will be added by the end of the year, making me one happy camper.
I have never given anything but a fleeting thought to return to DirecTV so I'm not sure where you're getting your info. Most everyone I know that's switched to FIOS plans to stay with FIOS for the long haul. My niece's husband has never been happy with any TV provider until he switched to FIOS. He went from DirecTV to Comcast to FIOS and he's finally a satisfied customer.
Bundling all four services gets me a better price on my TV service, and not just for a limited time. I do recall Verizon offering a lower price for the 1st year, but that's pretty much standard practice throughout the industry. DirecTV does it all the time with their freebies and incentives. I love having all four services show up on a single bill. It makes budgeting my monthly finances a whole lot easier. FWIW, I'd never set up automatic paymebnts for any creditor, regardless of how convenient I thought it might be. I do all of my banking online so it's easy for me to schedule regular payments when I want and not have some creditor dip into my account unnanounced. Once you give them access you lose any leverage for settling disputes because you've already authorized whatever payments they seem fit to charge you.