I think the value of a Wikipedia pageview may not be fully captured by data like this on its own, because it's possible that the majority of the benefit comes from a small number of influential individuals, like journalists and policy-makers (or students who will be in those groups in the future). A senator's aide who learns something new in a few years' time might have an impact on many more people than the number who read the article. I'd actually assign most of my probability to this hypothesis, because that's the distribution of influence in the world population.

ETA: the effects will also depend on the type of edits someone makes. Some topics will have more leverage than others, adding information from a textbook is more valuable than adding from a publicly available source, and so on.