Not to over simplify, but in my opinion the 2013 season comes down to one question: Can the Bills (with Pettine's new scheme) stop the run? If the answer is no, I see a record equal to or less than 2012. If the answer is yes, then options open up for discussion (can we put together an offense with similar potency as last years, etc).
My fear is that yes, we will stop the run (and overall have a much better defense), but that offensively we slip a bit due to a new QB, new OC, etc. But I will be happy with a middle ranked defensive showing while our new offense gels... 7-9 anyone?