Here's a closer look at the teams, a few of which I've become very familiar with over the last few seasons.
New Orleans Saints
Keys to victory: The number one key for the Saints on Sunday is the ability to protect Drew Brees, giving him time to read through his progressions and get the ball to the right receiver. The Saints have so much depth at the skill positions; it's difficult to defend all of them. Given time, with his accuracy and decision-making ability - which are both supreme - Brees can pick you apart. Brees needs open throwing lanes and clean looks down the field.
Defensively, the Saints need to stop Adrian Peterson and put the ball in Brett Favre's hands, hoping to get some pressure on him. The Saints need to force turnovers, and they have the master thief in the secondary with safety Darren Sharper. This is a big game for the former Viking, who has a lot to prove. If there's one guy I want playing safety in this game against Favre, it's Sharper.
X-factor: The offensive line will play a key role in this game. One, it must be able to protect Brees. Two, one of the keys against the Cardinals was staying balanced and running the ball. When you can do that, you force the defense to defend more options.
What to watch: It seems to me that Reggie Bush has decided it's time to take it to another level. I love the physical aspect of his game he displayed against the Cardinals. The look on his face and the way he attacked defenders was outstanding. Great performers step up in big games. He's primed to do that.
Keys to victory: The biggest keys for the Vikings are nearly the opposite -- can they pressure and rattle Brees, especially early? Can the Vikings handle the environment they're stepping into? I understand the Metrodome is loud, but in my opinion the Superdome will be the most electric crowd in the history of pro football. The Vikings have a mature team and can probably handle it, but we'll see.
If the Saints use Bush on punt returns, Vikings punter Chris Kluwe will be a key to this game. He'll have to be successful in keeping the ball outside the numbers, preferably right on the sideline. If you put the ball down the middle of the field, Bush is very likely to break one like he did last week. You can't give Bush open field to work with. Keep it out of his hands.
It sounds redundant, but I'll say it anyway: Favre needs to continue playing the game he's been playing all season. He's been doing a great job of avoiding the critical error. He's been in these games before and has years of experience, so if there's anyone who can do it, it's him. But he needs to keep his emotions in check.
X-factor: The Vikings have so many weapons I haven't mentioned, but Sidney Rice is the real deal. He's long, tall, fast and wins battles for the ball. He's fun to watch, but not fun to defend. As a young receiver, he's been infused with confidence from Favre. How the Saints decide to neutralize Rice, or which of the Vikings' weapons they decide to try to stop, will be key. If I'm Gregg Williams and I know I have an offense that can score points, I would chose to be more aggressive and attack Favre more. I know that my offense can match teams score for score.
What to watch: I like the way both of these defenses are playing, and the defensive coordinators in this game are very interesting. Williams has a base philosophy of bringing pressure, especially from multiple angles, and creating problems for the offense from different looks. On the other sideline, Leslie Frazier is someone who relies on the base cover-2 defense and fundamental football. Coming from opposite ends of the spectrum, Williams and Frazier have both moved toward the middle, developing their defenses. Both defenses are really clicking right now, and the coordinators have got them right where they need to be with the perfect mix. It will be something to watch.
Keys to victory: Something the Colts have done well all season is stop the run, and they have to do it again. The Colts need to find a way to put Mark Sanchez in third-and-long situations where he has to make plays with his arm, so they can come after him. Stopping the run has been an overlooked key to their success all season, and it puts them in a position where they can utilize their pass rushers and play zone, doing the things they do best on defense. Take away the Jets' strength.
The other key that I see is simple: Let Peyton be Peyton. It's key to protect him, because the Jets will bring a plethora of different pressures coming at him -- Rex Ryan knows how to play against Manning. But if there's any player in this league who is going to study endlessly to find all the idiosyncrasies of this defense, it's Manning.
X-factor: The Colts don't really have weaknesses. But by not letting the Jets control the clock, the Colts keep Manning on the field. That's when good things happen. If you're the Colts, you don't want Manning on the bench, unless it's to put a hat on because he just threw a touchdown. Watch the time of possession.
What to watch: There is no one like Manning when it comes to preparation for a game. He's the best in the game, and maybe the best that's ever played. It's one thing to look at film, but Manning has trained himself to know where to look, what to look for and to recognize things - he's like a coach that way. Then, he recognizes it on the field immediately. He's tremendous at in-game adjustments, from series to series, changing things on the fly. It's something to keep an eye on.
New York Jets
Keys to victory: Momentum and confidence are important for the Jets. If the Jets can keep it close in the first half and then come out in the third quarter and have success, their confidence will go off the charts. They have confidence right now, and need to maintain it. Trust me, Ryan knows it, too.
X-factor: Everyone talks about Darrelle Revis and the matchup with Reggie Wayne, but how does Lito Sheppard hold up in this game? If Ryan puts his cornerbacks in one-on-one situations, Sheppard is a key. He's overlooked, but Sheppard is a very good player a lot of teams would like to have. A good game would allow Ryan to be more exotic with the Jets coverages.
What to watch: It's important for the Jets to disguise their intentions on defense. Not their coverages, but what they intend to do. They have to disguise what they want to do pre-snap, forcing Manning to make decisions with the ball in his hands. If he has to diagnose what coverage the Jets are in after his drop, that fraction of a second can make the difference.