The social network now accounts for 3.1% of all searches, which marks a 46% increase from 2010.
Facebook also reigns over the top 10 list in the US, with four variations of the term among the top 10 items. These terms put together account for 4.42% of overall searches, showing a 24% increase from 2010.
YouTube is now the second most-searched item in 2011, moving up from third spot in 2010. Third is "Facebook login" followed by "craigslist" and "facebook.com".
There were also new terms that made the top 50 list for 2011, including addicting games, amazon.com, cnn, chase online, face, facebook sign up, hotmail, lowes, pandora, twitter and you.
"Navigational searches dominated the top search results as users typed in terms versus typing in the URL in the browser bar," said Simon Bradstock, general manager of Experian Hitwise.
"Hitwise saw 11 percent growth of single-word searches in 2011 as terms like 'face' and 'you' made the top 50 searches. Marketers need to be particularly brand-savvy when managing their search optimization campaigns because of this behavior, which is a result of predictive search functionality across major search engines.
"Other top 2011 searches reflect ongoing fascination with celebrities online, and many of the top fast-moving searches centered on natural disasters or notable personalities passing away," he added.
When it came to websites, Facebook again reigned, with Google.com coming in second, followed by YouTube, Yahoo! Mail and Yahoo!.
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