'Pretty Little Liars,' 'Thor,' Charlie Sheen Are Top Twitter Topics of 2011

As 2011 nears an end, Twitter compiled a list of the top topics on its website for the year.

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In television, ABC Family's mythology-heavy teen drama Pretty Little Liars was the No. 1 hot topic, according to the company, topping its ranking from the previous year when it ranked second.

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That may come as a surprise since the hourlong drama, returning for the second half of its sophomore season in January, has hovered around the 3 million viewers mark thus far this season -- just a small percentage of the audience that tunes in to CBS juggernaut Two and a Half Men, which came in No. 2 this year with the help of Charlie Sheen's high-profile ouster and the casting of heavy Twitter user Ashton Kutcher.

It's no surprise then that Sheen was Twitter's most-talked about actor for the year; Kutcher was eighth. Ricky Gervais was No. 4 following his controversial Golden Globes hosting stint at the beginning of the year and Tracy Morgan ranked sixth, most likely due to his homophobic rant.

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Lifetime telepic The Craigslist Killer followed Liars and Men as the third most-talked about TV event, with the Golden Globe Awards and People's Choice Awards at fourth and fifth, respectively. Craigslist Killer, based on the real-life story of med student/National Honor Society member Philip Markoff who was accused of killing a woman he found on Craigslist, drew 5.4 million viewers in January.

On the film side, the four out of the five top topics of the year were genre films based on beloved characters. At the top of the list was Chris Hemsworth's summer blockbuster Thor, followed by the heavily-reported Batman threequel The Dark Knight Rises with Christian Bale, X-Men: First Class, actioner Fast Five and the Seth Rogen superhero turn Green Hornet.

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Actresses like Mila Kunis, Anne Hathaway, Natalie Portman, Jennifer Lopez, Nina Dobrev and Emma Watson were all topped by Elizabeth Taylor, who died at the age of 79 in March.

Rebecca Black and her song "Friday" dominated the social media site in music for the year. (Katy Perry's "Last Friday Night (T.G.I.F.)" music video featured Black.) Nate Dogg followed in second and Britney Spears' Femme Fatale was No. 3.

Interestingly, What the Trend? released the top 10 trending topics on Twitter and reported that Justin Bieber was No. 1, with Lady Gaga third, the Jonas Brothers fifth, South Korean boy band Super Junior at No. 7, Britney Spears eighth and a U.K. boy band One Direction at No. 10.

In their list (data was compiled Nov. 30, 2010 to Dec. 1, 2011), Glee, Saturday Night Live, The Vampire Diaries and Jersey Shore were in the top five among U.S. television shows. Harry Potter took up two spots in movies, while Phineas & Ferb telepic topped Twilight.