I don't really see a superior contender. Every contender has looked terrible at times. Injuries to key personnel have been a factor and could be more so in the playoffs. I'm very interested in the SF vs Seattle game this week. Denver has played a weak schedule. Green Bay destroyed Houston at home. The Giants haven't looked like a SB team. Atlanta is good and lucky as well. The Pats are always dangerous with Brady playing. Which team will have a hot QB and an intact defense going in and can remain relatively injury free will be my pick.
I forgot Denver. I think they will win the AFC.
http://espn.go.com/nfl/playoffs/machine
Playoff calculator, you can see who makes it in with your predicted game results.