Because of the nature of Twitter this story's not going anywhere. The culture of Twitter is "if you follow me I will follow you back. If you unfollow me I will unfollow you".
Obama is listed as one of the "celebrities" who follows back. That means his twitter account is set on auto-follow like mine.
Heck, even I may be following that account and not know it. I never checked.
Oh, well now...if your the prez don't you want to make sure your not following something unbecoming?