Actually the Green Bay Packers were ranked No. 2 overall last week too, and they remained unchanged in this week's SB Nation NFL Power Rankings. It's a tangled group of 7-2, 6-3 teams (Falcons, Eagles, Saints, Giants, Buccaneers, and Bears) in the NFC, but the Packers have the best point differential in the NFL. They've allowed the fewest points in the NFC, and have scored the 4th most (only behind the Eagles, Giants, and Falcons).
From Joel Thorman:
They've allowed seven points in their last two games. It's looking like the season finale against the Bears may be a big one.