Zuckerberg has certainly earned the attention he's received over the last few years, for better or for worse, but my first thought when I'd heard that TIME named him PotY was, "What a pedestrian choice." Safe and boring.
Granted, this is the same news organization that declared "You" to be their pick for Person of the Year previously.
I suspect that you are implying that Julian Assange must had been the TIME's Person of the Year 2010 and not only the Readers' Choice Winner and I clearly agree.