http://news.bbc.co.uk/1/hi/technology/7488009.stm

Google must divulge the viewing habits of every user who has ever watched any video on YouTube, a US court has ruled.

The ruling comes as part of Google's legal battle with Viacom over allegations of copyright infringement.

Digital rights group the Electronic Frontier Foundation (EFF) called the ruling a "set-back to privacy rights".
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Sigh