Alex Lundry, Vice President and Director of Research of the consulting firm Target Point, has published a brief talk called Chart Wars which is simply brilliant, serving as an excellent but brief (5 minutes!) overview of how easy it is to manipulate infographics and what tricks to be wary of. His specific focus is a chart (which was covered on TGR previously) whose designs - and it went through many iterations - were politically motivated. While there is no doubt about which charts are more clear, his implicit question - which charts are right? - resonates philosophically.
Here's the video of his talk:
(Via Information Aesthetics)