Well it seems to me that if x% of 1 billion people's income (take China or India for instance) goes to the same organization, that's pretty centralized monetary power.  Sure, the number one goal is to prevent central bankers from toying with the money supply for their own ends, but really whether it's through inflation or taxation, the current monetary system enables theft.  And as far as I understand it, that's what bitcoin was designed to stop.

I don't think it's possible to legitimize bitcoin in the eyes of governments whose operation rests on constantly inflating the money supply.  And I'm unconvinced that the people who worry about paying taxes will see bitcoin as legitimate when government is publicly decrying it.