After watching this video and reading the article I think that Mar is just a normal guy. It seems to me that he was never searching for fame and fortune. It kinda just fell upon him which I think is the best kind of person to put into a position of power. This means he's not power hungry and hes not selfish and money driven. He was in university doing a project that just happened to blow up into the largest, most popular social networking site in history.
The fact that he doesnt blow all his money on buying a huge house, cars and other meaningless material objects just means hes smart. Hes saving for the future and doesnt want to draw lots of attention to himself or his family. I'm pretty sure I would do the same thing because he doesn't strike me as the type who wants to be a celebrity. By keeping everything quiet he is ensuring his families safety and his privacy.
People are speculating that the only reason he is making a donation is to get attention to boost up his up and coming film. They think he wants to advertise it even more to make more money. I think that the kid just didnt know what to do with all the money he has already and will continue to be getting. His timing of the announcement of the donation shouldnt matter. Personally if I was one of those kids in New Jersey getting all this money I wouldnt care if he was doing it to be nice or to advertise a movie. Money is money and its gonna do the same thing regardless of how it got there.