If the NFL playoffs started today, four of the six teams in the NFC would be different from a year ago, while three of the six in the AFC would also be dissimilar.

Teams with such high preseason expectations such as Tampa Bay, Tennessee, Denver, the Giants, Minnesota and Indianapolis would not make the playoffs.

So is it any surprise that the new No. 1 team in the SportsLine.com Power Rankings is a team that didn't even make the playoffs last season? With apologies to the Oakland Raiders, who are playing very good football, the new top team is the Pittsburgh Steelers.

QB Kordell Stewart and the Steelers are on top of the heap.(AP)

The Raiders and Steelers are both 8-2, tied for the best record in the AFC, but there's an easy explanation as to why the Steelers hold the top spot. Their team strength is defense, while Oakland's is offense. That said, the difference between Pittsburgh's defense and the Oakland defense is greater than the difference between the Oakland offense and the Pittsburgh offense.

Oakland is second in the league in scoring to the St. Louis Rams at 27.9 points per game, but the Steelers actually have an edge in total offense. The Steelers lead the league in scoring defense and total defense. Oakland is ranked 13th in total defense and 14th in scoring defense.

Edge Pittsburgh.

Both teams have lost a game they should have won. Oakland should have beaten Miami on the road, while Pittsburgh should have beaten Baltimore at home, losing when kicker Kris Brown missed four field goals.

Push.

The 266-yard rushing performance by Seattle's Shaun Alexander three weeks ago against the Raiders is the one real negative that stands out for both teams.

Edge Pittsburgh.

So it's the Steelers who take over the top spot from the St. Louis Rams. The Rams fell 24-17 to the Buccaneers on Monday night in a game they literally gave away. St. Louis had five turnovers to give the Rams an NFL-high 32.

That's not the type of play that will win a Super Bowl. St. Louis is now tied with the 49ers atop the NFC West, although the Rams have the tiebreaker edge having beaten the 49ers once.

Heading into Monday's game, the Rams appeared on the fast road to the Super Bowl. The loss means they have a huge game coming up with the Atlanta Falcons (6-4) on Sunday at the Georgia Dome. An Atlanta victory, coupled with a San Francisco victory over the Buffalo Bills, would put the Rams in second place.

It's funny how a span of seven days can put a quick end to any team even thinking about making Super Bowl arrangements. There is nothing given about this season.

The Steelers have the top spot for now -- just barely. But the Raiders, 49ers, Rams, Jets, Bears and Packers all have a chance to have it in a week or two.

Just looking at that list of potential top teams is a sign of how much things have changed since the 2000 season. The Jets, Bears, Packers and 49ers weren't even playoff teams a year ago, but they now have a chance to be the top seed in their conference and the No. 1 team in the league.

Pittsburgh currently holds that spot. But as the Rams are finding out, things can change quickly in a league where there is no real power team.

The Power Rankings for Nov. 27: