Let me get the nitpicking out of the way and then end with praise. He's wrong on three counts.
One, Obama did take a stand on gay marriage during the campaign. He opposed it. Two, barring gays from the military hasn't gone by the wayside. There are still hundreds of gays and lesbians expelled from the military every year. And three, as a nation same sex marriage isn't recognized, but on a state level there are several states that do now recognize gay marriage.
With that said, I give major kudos to Ayanbadejo. He's a current player in a sport that's notoriously macho and homophobic. Coaches and players in this league are not known to be overly enlightened. They're more likely to use the words "faggot" and "sissy" to negatively motivate players.
He goes out on a major limb by standing up for gay rights. Of course he's probably anticipated that this will prompt some to speculate whether he is gay himself and he's prepared to deal with that. I wouldn't make that assumption but some will.
Let's hope once this dam has been breached, others in the NFL will publicly express a more accepting stance also.