fivethirtyeight's current ELO rating has them sitting at 8th.
The Bucs ELO score cluster (two teams below Seattle) through Green Bay (four teams above Seattle) is reasonably tight. The top three teams above that have a much higher score.
Given this teams very high PPG allowed and low point differential, they have a lot to prove in the closing weeks to be comparable to the Chiefs, Saints, and Steelers. Among the Packers, Colts, Rams, Ravens, Bills, and Bucs, who knows.
If this defense plays more like they did last game and in the first half against SF, then they could be among the best teams. But if they put up several more games like they have played almost all season I don't think you can look at them and think they're easily one of the top teams in the league. They're still good and will make the playoffs and you never know if they'll just get a 2011 Giants kind of streak going, but come on.