One is that they both played USC at home. Ohio State lost on a last minute touchdown, while Oregon blew out USC and trampled all over their defense.
The second is that Jim Tressel has suffered notable losses to option quarterbacks, and at least struggled more against them than they do against conventional attacks. Losses to Vince Young, Illinois two years ago, and the near to defeat to Navy (Navy?!) at home highlight his teams struggles. I think it is a combination of the rarity with which they face option attacks and simply a facet of Jim Tressel's coaching philosophy. He doesn't like to take risks, he doesn't like uncontrolled chaos, etc., that the option attack is more lethal than normal against him. He recruits players and coaches them to do specific functions really, really well and he tries to keep the game within those parameters. He's had a lot of success doing that (one national championship, three national championship appearances) but has also seen his teams struggle against the spontaneous playmaking and athleticism of spread and option attacks (like the loss to Florida).
This will require more thought and analysis, plus a return to Bleacher Report is called for!