I actually think that the addition of Favre might disrupt some things for AP. I know this is contrary to popular opinion (and for the record I have AP ranked #2 on my draft board and will take him in a heartbeat). I think Favre, especially an older, desperate Favre will try to force too many things too often this year with bad results. I can't see him content to hand off constantly to AP. If the D stacks the box Favre more often than not would audible out of a called run where as previously they might have tried to force the issue, banking on the talent of the RB. Of course having a guy like Favre allows AP to not be the focus of defenses as much as previously.
All this to say that I think he's worthy of a top pick but I wouldn't be surprised to see him underperform somewhat...his underperforming being better than 80%+ of the backs in the league. I just don't think he's as much of a lock as most are assuming...but you have to play the odds soooo...yeah, go ahead and pick him 1st.