Is their a much greater parity among the top teams in the NFL this season than in recent years?

Is it just me, or has Green Bay, Dallas, Indy, and New England distanced themselves greatly from all other teams in the NFL? Does this year seem like no other team outside of these 4 stand a chance to win the SB or even go to it?! Can you recall recent seasons where the difference between the great teams and the good teams seemed to be so much?