The story of the missing time at Columbia is old. You are right about that. But what is new is that on June 9, an article was published stating that a well known professor (retired) from Columbia said he didn’t remember ever having Obama in his classes, and that Obama would have had to take one of his classes for his major.
From 2012:
http://www.wnd.com/2012/07/record-shows-obama-at-columbia-only-1-year/
...Graff further told WND no professor he knew could remember having Obama as a student at Columbia.
“Nobody I knew at Columbia ever remembers Obama being there,” Graff insisted...