According to wordpress there are over 32 million WordPress publishers as of December 2010 and 16 million blogs hosted on WordPress.com plus 16.7 million active installations of the WordPress.org software.numbers are for WordPress.com hosted blogs only.
According to Quantcast, over 260 million people worldwide visit one or more WordPress.com blogs every month, and they view over 2.3 billion pages on those blogs each month.
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