This is a really smart essay that raises some fascinating points. What I find most intriguing is the way that you present pragmatic questions--such as, how does one fund these projects?--as being intimately connected to more philosophical questions, such as, whose material deserves to be archived and why?
Your comments in this essay about how we determine who we do (and don't archive) made me think back to one of your earlier responses to the roundtable questions where you suggest that the Whitman Archive be more transparent (and provide more current data) about how many people are actually using the site. How might this data about who is using these sites help to address the question you raise about "whether one historical figure is more 'deserving' of such a site than another"? I don't want to suggest that archivists base their decisions on site traffic alone (which would, in effect, turn digital archives into a twisted version of scholarly "American Idol"); rather, I think what I'm saying is that this data needs to be on the table as these decisions are made and these issues are debated.