In Chicago, quarterback Rex Grossman, injured and out since early in the season, has transformed the Bears into an assertive passing-team winner since he came back.
In New England, the Patriots, also back from injury, still have their Super Bowl core. Coach Bill Belichick keeps the game close, quarterback Brady leads the last decisive drive, and Adam Vinatieri kicks for the win.
The Bears and Patriots share one more thing in common. With interest, both are awaiting the details of wild-card weekend's feature attraction today, Pittsburgh at Cincinnati.
The NFC's best team, Philadelphia, lost its Super Bowl shot in the first quarter of its first game last September when Donovan McNabb went down in Atlanta.
A late hit by a Falcon nose tackle, Chad Lavalais, left the Eagle quarterback with a severely bruised sternum.
Struggling on for several weeks, McNabb was repeatedly re-injured and eventually went into surgery as the Eagles went out of contention.
Thus, a late hit four months ago determined the pairings for Super Bowl XL.
With a sound McNabb, the Eagles had been a playoff team, and a Super Bowl team just last year, when they lost to New England by three points. The reality is that with the real McNabb, they dominate the NFC.
The Steelers rode into Ohio this week on a wave of late-season momentum, whereas the Bengals seem to have come unglued lately, indicating a Pittsburgh triumph today
The Bengals' only shot is to play a superb and intensely physical game, which they did last month in Pittsburgh, where they won, 38-31
That evened the 2005 series, since the Steelers had won an earlier game at Cincinnati, 27-13.
The Bengal edge in pass-receiving speed is huge with Chad Johnson and T.J. Houshmandzadeh to Hines Ward, but Pittsburgh's defensive power will tip the balance -- barring Cincinnati's return to the defensive excellence it showed earlier.
The Steelers have the edge in coaching experience with veteran Bill Cowher over Marvin Lewis, who nonetheless remains a candidate for coach of the year.
On their best days, Cincinnati's defensive people have proved they can stop any running game, even Pittsburgh's, but it's very hard work for a lineup of less than all-pro players, requiring a supreme effort in every position.
They might not be able to get that again, particularly when they also have to deal with Roethlisberger, who has apparently come back from injuries.
The Bengals' meltdown in recent weeks, after a flying 11-3 start, suggests that under Lewis -- who also came undone last month -- they've figured out how to play NFL football but not yet how to win big.
The Giants have been pulling out the close games this season with their new quarterback, Eli Manning, who is unlike brother Peyton in two critical respects.
As a passer, Eli hasn't been consistent but has played superbly in the clutch.
At Indianapolis, Peyton, by contrast, plays with consistent excellence when front-running but hasn't prevailed in playoff pressure.
Whoever wins in the Meadowlands today, Manning or Panther quarterback Jake Delhomme, surely can't expect to win again this year, for these are two flawed NFC teams -- good but less than super.
Under famously conservative coaches, Tom Coughlin of New York and John Fox of Carolina, both are unreliable passing teams.
The Giants do have two advantages that are likely to prove decisive. Their running back, Tiki Barber, is usually the best player on the field and will probably have that distinction again. And Coughlin is somewhat less conservative than Fox.
Coughlin has, in fact, turned over much of the offense to his assistants, who have a lot of good ideas that Manning can't yet quite execute, although he's served by rangy, aggressive receivers, 6-foot-3 Amani Toomer and 6-5 Plaxico Burress.
His 6-5 tight end, Jeremy Shockey, has had some injuries.
On the Carolina team, Fox, as a heritage of his 2004 Super Bowl appearance, still interferes too often in the Panther offense.
A classic throwback run-and-defend-the-run coach, Fox can't get his running game going the way he wants it. That puts too much of the load on passer Delhomme to suit Fox.
A big-play type, Delhomme hits some and misses some.
Kansas City is one of three prominent teams that missed the playoffs after starting the season with the resources to get there. The others are, of course, Philadelphia and San Diego.
The Eagles missed out because they never had the real McNabb.
The Chargers failed because they played too timidly in a series of close games that were lost -- most of them agonizingly close -- and most of them winnable with a more assertive offensive approach.
The Chiefs fell short because, again, after all these years, they were all offense and no defense. Dick Vermeil's marvelous offense was hard put to outscore his defense.
That's a reminder that the great offensive coach of our times, Bill Walsh, was forever strengthening his defensive lineup.
The only team that's ever held together to win five Super Bowls, the 1980s San Francisco 49ers, did that only because Walsh built the first great modern passing machine and combined it with a continuously effective defensive machine.
In this era, such a thing is harder to do, but in any case the Chiefs solved only half the problem.
They might still have reached the playoffs if the best running back in the league, Larry Johnson, hadn't spent the first half of the season on the Kansas City bench.
It's difficult to fault Vermeil for overlooking Johnson when he had Priest Holmes, another great offensive back -- but the fact remains that Johnson is the more productive.
At the least, had Johnson divided the snaps with Holmes, the Chiefs would have been tougher because as ballcarriers, they're two such different types.
It wouldn't have been easy to prepare for an outside threat like Holmes and an inside man like Johnson in the same game.
With Johnson as their starter, the Chiefs had an offense that in three respects was unique and productive.
First, they had the league's best offensive line. Second, Johnson showed more speed plunging into and through the line than any other active running back. And third, after he got through, his moves and speed were comparable with those of the league's leading open-field runners.
The least satisfactory thing about the playoffs is that with Johnson absent, fans won't see the finest the NFL has to offer.