I don't see how anyone can read this blog post by Markus from 2006 about faking site traffic rankings and not think his current traffic stats are severely manipulated.
Isn't that post about how he tried to prohibit people with the alexa toolbar etc. to enter his site? This would actually decrease the number of pageviews these services would show for pof. I wouldn't consider this an argument not to believe his own numbers by now.
http://plentyoffish.wordpress.com/2006/06/14/competitive-int...
I'm not saying I don't respect what Markus has done. I just don't think his stats are anything near what is reported.