John Craig has a short piece about the project in the current issue of Pittsburgh Quarterly (the article is not online):
[J]ust because a blogger or a Congressman or a pundit cites a piece of data, it does not follow that it means what he says it does. Nor, and more important, that it means anything at all. A datum, accurate and attributed though it may be, is too slender a reed upon which to hang very much, least of all significant matters of public policy. A decent sense of reality demands relevant and comprehensive data in context. That last means a 10-year record if at all possible and some standards or comparables for purposes of measurement.
That's a sensible statement, but don't be misled by the appearance of impartiality that comes with "data." "Data" means counting things. Choosing what to count, and choosing what "context" is relevant, makes all the difference. Do pay attention, in other words, to that man behind the curtain. Demographers, economists, and statisticians can supply the raw materials for narrative, and at times they can weave persuasive stories, but assumptions are their lifeblood. Pittsburgh Today looks like a useful resource -- but always examine the assumptions carefully.