Great visualisation demonstrating the relationship between actual US budget contract spend and media representation of those areas.
The blog has an excellent explanation of how the work was constructed and the viz iterated.
And then there's an interesting "why this is rubbish" type of post by Stephen Few here:
(with a joyous interchange of comments...)
Overall if something makes you stop, look, go woah, and then go about your business then that's quite effective I think. It depends whether, as Stephen suggests the goal is to extract meaning, or simply make a point.
Headline journalism versus investigative journalism only with pictures...
Tabloid data viz versus Economist data viz?