Quantcast's Mobile Site Rankings Not Credible

I was unaware that Quantcast offered a ranking of top US mobile sites as well as PC sites until today. The metrics firm's PC site rankings are credible and generally consistent with other, similar rankings from comScore, Hitwise and Nielsen.

However the mobile site rankings seem completely incorrect to me. I just don't buy them.

First, here's the list of Quantcast's top PC sites: Google, Facebook, YouTube, Yahoo, etc.

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Below are the company's mobile rankings. Clearly Answers.com is not the top mobile website in the US. Where are Google, Facebook, YouTube, Yahoo or Wikipedia? These are top mobile sites in the US and globally according to Nielsen and Opera

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