An NFL executive once said that in order to evaluate a QB you must look at him and say "can he lead your team to victory in the 4th quarter of a Super Bowl". Everyone at this point obviously knows the answer to that for Eli, and that obviously is yes. Eli in the big spot is great, we all know that. In this years Super Bowl he became the 2nd QB ever to throw 2 touchdowns in the 4th Quarter, the first is Joe Montana. That is pretty good company for Eli Manning.
The problem for Eli and the Giants was not his play in the playoffs, but rather his play in the regular season. The way I look at it is he played his best ball against the Patriots and Cowboys who were the top seed in each of their respective conference. In these 5 games, including playoffs Eli threw 13 touchdowns, which is at more than 2 a game, that pace could result around 41 or 42 touchdowns for the season. That would then put him up there with his brother Peyton and Tom Brady for what could be the tops in the NFL next year.
In six games aginast 7 or 8 win teams last year (Lions, Vikings, Bears, Bills, Eagles (twice)) he threw 5 touchdowns in 6 games. We all know that those type of numbers will not help the Giants achieve greatness again.
Manning needs to show that he can avoid the pesky fumbles and interceptions which really hindered the Giants offense at times last year. If he is able to limit his mistakes then the Giants offense could click on all cylinders. The run game will be able to be dominated by Brandon Jacobs, Ahmad Bradshaw. The O-line will be able to block as a cohesive unit. Manning has a wide array of talent on offense and if he plays consistently well the team will make the playoffs and possibly go to repeat.
What I think Eli will do next year? He will probably pass for 3700 yards, 26 TD, 14 INT. That should be enough coupled with the Giants defense for them to win 10 or 11 games even in the toughest division in football of the NFC East.