The short answer is that Missouri played a 0-5 team, while Rutgers played a 3-2 team. Computer rankings do not take into account if a team "barely" beat another team. Just that they beat them. Margin of victory does not factor into the computer polls used for the BCS. Also, the poll doesn't remember what each team was ranked last week. It doesn't move them based on their relative position to other teams. It simply computes who has the best record while playing the best teams.
Regardless of whether it remembers, that kind of drop doesn't make sense. My point is that the equation you're using could probably use some heavy tweaking if a team is able to fall 15 spots after a win.
As a Rutgers Alum, I can say that the seven spot seems a bit high. I like the poll, but it seems overly partial to tough schedules. The addition of the 0-5 record to Missouri's overall opponent's winning percentage knocked that component down a lot.
These polls are really tough early in the year, but once the BCS teams get deep into their conference games, things usually clear up.
