The hatred between Ohio State and Michigan is a lot older than the Internet. It is probably the most (or at least one of the most) intense rivalries in all of North American sports.
Michigan wasn't doing so hot before Bo came up north. The coach before him went 51-42-2 from 1959 through 1968 (2-7-1 against Michigan State and 3-7 against Ohio State). They won on Big Ten title in 1964 and won the Rose Bowl over Oregon State after that season. Otherwise? Meh.
They fired him (Bump Elliott) after Ohio State beat them 50-14 and went and got Bo to turn it around. Bo was born in Ohio, played for Miami-Ohio, was an assistant coach for Ohio State and Bowling Green State before becoming the head coach at Miami-Ohio and then moving up to Ann Arbor.
Sorry, but there simply is a major precedent of an Ohioan saving Michigan football out there. The situations really are not all that different -- Woody won two natties during the 1960s.
I do not think Campbell is leaving for Michigan. I do not think they are about to fire Harbaugh. But the precedent of looking south for somebody (e.g., Luke Fickell or Campbell) is there.
Heck, McCarney was a Hawkeye right off the Fry tree, and now he's one of our beloved elder statesmen.