I usually don't pay attention to this because Manning seems to be the anointed one every year but Troy Brown made an interesting comment and it got me thinking.
So everyone marvels at Manning calling the offense at the line and the command he has but Troy made the point that he thinks no one does more than Brady because Brady is asked to run a different offense from week to week and year to year. One week it might be a spread offense with a certain receiver group. The next week it might be a bunched offense, a run and shoot offense, etc. In other words, Brady not only has to be on top of the offense, recognize the defense, and control protection, but he has to do this for completely different offenses, groups, and concepts from week to week.
With Brady, it's not enough to master "the offense". Every offense has basic concepts that are used as the basis to exploit certain defenses. Brady is asked to constantly play different concepts, packages, and blocking schemes because the Patriots change from week to week. His backs change. His receivers change, and the matchups and ways to exploit them change.
I really think Troy hit on something that I hadn't considered before. It's the way that Brady can play a variety of offensive styles at such a high level and with so few mistakes while everyone fawns over Manning because he makes the same audibles at the line he's made for 15 years and plays the same offense regardless of the opponent. Don't get me wrong, the fact that Manning executes it so well makes him special but I now reject the notion that Manning does "more". I think that's crap.