Only the people who worked at Harvard at that time. And the students at that time who would have known about Obama. Here is a video that supposedly is genuine showing Obama at Harvard:
http://www.youtube.com/watch?v=tz3qShugQ9I
I think the video is fake! And that the sloppy PDF of Obama's birth certificate is done so on purpose as a conspiracy bait to distract people. The really hardcore fakery is this video. Then of course is the question, why the image of Obama at Harvard is such a poor fakery. Could it be a double conspiracy bait? lol. That there is something else about Obama other than the birth certificate or the Harvard studies they are trying to hide.
Could that video really have been faked? Yes, with today's computer graphics I guess. It would require fairly professional editing tools but it could be done no doubt. Here is a more obvious fakery with computer generated cars but fairly good too:
http://www.youtube.com/watch?v=SnWC0tFXtcw