Big 12 wasn't as expected in postseason, yes; but Ohio State and Michigan State can't completely make up a lackluster regular season. Illinois made a bowl game last year... Illinois. The talent discrepancy between the two leagues isn't even close, and one good OSU season, or a bad Big 12 bowl season won't change that. Schools like Mississippi State and TCU have more talent than Michigan and Nebraska anymore. Its not really a Big 12 vs Big Ten argument... its North vs South, and both of our teams are suffering as a result.
Isn't close? In last year's draft the B1G had nearly twice as many players drafted as the Big 12, 30 to 17.