actually if your point was "Tumblr Doesn't Leave Posterous in the Dust " the misread does kind of kill your whole post.
Daily pageviews here is probably the least useful metric to evaluate our site, given that Posterous doesn't chase pageviews and send daily subscription emails (full text bodies) to users directly. Users can also reply to comments via email without ever going back to the site. The monthly numbers are much more in line and reflect the way our users use the site.