No, I do not believe that the NFL power rankings determine real ability. I think that every team plays different at every game and it is really only determined on how well our team mates play with you. Every team has hope. I just believe that the NFL power rankings HELp to see the ability in the teams.
NFL power rankings determine real ability. This is because they are based on performance. Although evaluating people and basing their abilities on some specific standard is often looked down upon by people who don't believe in tests, the NFL knows what it is doing with regards to the skill of players and their value in the NFL.
Power ranking have a kernel of objectivity, in that, for example, no one would rank the Jacksonville Jaguars or Oakland Raiders number one. However, in addition to being subjective, power rankings and eminently ephemeral. As of October 28, 2014, the Denver Broncos top most lists. That gives them no advantage in any subsequent game. If they lost the next three weeks, then everyone will readjust their rankings and the process continues.
The NFL power rankings are a great way to quickly see who's doing very good this season, although even though it looks good on paper and on the Internet, it doesn't mean it is 100% accurate with the players ACTUAL abilities. I don't think they reflect the real rankings that would be available if we did it another way.