WordPress Usage Statistics. Can you believe it? As of March 2012, WordPress is on 72.4M sites! Global Phenomenon, Wordpress Stat, Website, Web Site, Social Media, Wordpress Business, Wordpress Infographic, Internet Site, Stat Infographic
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Anatomy of a Wordpress Theme (not really technology but seeing as I could have used this info when I was setting up my Assistive Technology blog I'm pinning it here).