Tom Brady is currently the MVP by a HUGE margin based only on his on the field accomplishments.
If the voting were held today he would win unanimously.
While this would be true in most years, he is bolstered this year by several factors:
1. After Tom, NOBODY is having a really exceptional year.
Randy Moss would be up there if he weren't getting fed by Tom Brady (and his performance is slipping now that he is being double covered anyway).
Adrian Peterson is having a great year, but offensive rookies of the year don't often (ever?) win the award.
Nobody else even deserves special mention.
Peyton Manning is having a sub par year. Many voters would put Big Ben, Tony Romo or Brett Favre ahead of him. I think he's still the second best QB in the league, but I might put Reggie Wayne ahead of him.
2. Tom is "overdue" for the award. In a normal situation this would merely help his candidacy, but Tom's new receiver indicate to many that his performance in past years has been badly hampered by poor receivers. Since his performance has been under recognized in the past, there will be a tendency to over recognize it now. Bad Feelings towards the Patriots will play a role, but a minor one in comparison to the feeling that he is overdue.