Both my tow vehicles have been GM. I had an '09 GMC Sierra 1500 which was a very reliable truck for the time that I had it (80,000KM. There was an issue with lifters sticking which I believe was also my fault for not respecting the oil change schedule - fixed under warranty.
I had the front bumper develop premature rust which was also fixed after warranty, but was a known defect.
My newest TV is a GMC Sierra 2500HD and I have yet to have any issues with it. It has 30,000KM on it.
My brother in law owns a new (2012 or 13) Ford F-150 EcoBoost which is a surprisingly capable engine. It has, however, had a number of recalls, mostly due to condensation/turbo and exhaust issues. He still likes his truck.
I think either way, all brands have their qualities and as was mentioned by Campfire, these companies are just doing a better job of addressing potential quality control issues and hazards. Whichever you choose, enjoy it and care for it.