And it is clearly not a big deal in itself. However, it is symptomatic of some larger points. We know very little about the true biography of a President who was elected on the basis of his biography, and, perhaps because the gloss is so pretty and so historic, the press has not shown much inclination to seek the truth.
At the root, i suspect that many so-called birthers do not really care where Barak Obama was born. But they do understand the truth of Maguire's point. So, like a good transgressive performance artist they look for a way to shock and mock. Birtherism is a way to tweak journalists for their sloth and liberals for their gullibility.