I think its way to early to define whether Freeze or Mullen has done a better job. The circumstances around their first year are vastly different. In Mullen's first year, he had a 5'9" Tyson Lee QBing the team, and also faced a schedule with Florida, Bama, Auburn, LSU, ARK, GA Tech, and Houston. Auburn and Ark, both of OM's SEC wins this year, were much better then, and, while OM has had to play Texas this year, a loss is a loss, and GA Tech and Houston, are two tough wins where as Texas was only one tough win.
Freeze, has done a good job, but inherited a more talented roster than Mullen and has had a much easier schedule. If Freeze had Mullen's '09 schedule this year, he would likely only win 5 game or less. Just like Mullen.