Open data a difficult concept for some organizations to grasp. You'd think, tho, public agencies would be among the first to come to it. It's encouraging to hear of one who seems to be remembering the public part of their mandate. Props to Boston's MBTA.
Content of the highest quality can be seen as advertising for other work by the same producers. Public expression seeks an audience that wants more, that will remember the name (or brand), seek out further contact with makers, further information on the subject.
While it's possible to dissect subsets of content, I think it's important in this discussion to remember that we can draw no meaningful general distinction between advertising and any other media expression.