Last year it was because College Football cut out actual game time on the field to shorten games. However the games were not shortened and more commercials aired instead. I'm going to say that again; College football cut out playing time and replaced it with commercials. They watered down their product publicly. The NFL has maintained the integrity of on field playtime and has limited advertising timeslots.
This year I'm shifting more away from college because of the shameless control the television networks have over the sport. Everyone but the SEC and Big Ten are being pushed out so it seems like a waste of time to invest myself in something that's working against my fandom. In contrast the NFL operates as a centralized organization with a strong grip on the television networks. The league's centralized power ensures that networks align with the NFL's goals rather than dictating terms.