March is said to come in like a lion and go out like a lamb, but in social media at least, it came in like a tiger blood-infused Charlie Sheen and went out like a modestly talented 13-year-old girl.

Sheen’s public meltdown was one of the top trending topics of the month on Twitter, according to our friends at What The Trend. Sheen’s series of social media activities — joining Twitter, breaking the Guinness World Record for reaching 1 million users in the fastest time and then using his Twitter feed as advertising — consumed social media conversations early in the month, but then faded out.

Unlike Sheen, whose public falling out with his Two and a Half Men producer and the network were brewing for some time, the month’s other big curiosity, Rebecca Black, seemed to come out of nowhere. The likely impetus for the 13-year-old’s fame was Tosh.O’s blog, which cited Black’s video “Friday” on March 11 with the headline “Songwriting Isn’t for Everyone.” Black’s video, now at close to 70 million views on YouTube, had just the right so-bad-it’s-good vibe to ensure its viral success.

While Sheen and Black dominated a lot of discussion in social media this month, it’s heartening to see that they didn’t eclipse the unthinkable tragedy in Japan, which continues to be a major topic of discussion.

For the full list, check out our chart below. Because this is a topical list, hashtag memes and games have been omitted from the chart.

You can check past Twitter trends in our Top Twitter Topics section.

Rank	Topic	Intensity	Description
#1	Japan Earthquake/Tsunami	5	A massive 8.9 magnitude quake hit the northeast Japan at approximately 2:46PM local time on Friday, March 11th, causing devastating flooding from 10 metre (32 feet) tsunamis that hit the eastern coastline . The tsunami also affect countries around the Pacific rim. There also has been ongoing concern about variations in radiation levels at several nuclear reactors around the county.
#2	Rebecca Black	4	Rebecca Black is a 13 year old singer from Orange County, California with a music video on YouTube that many people find amusing or annoying. Her video has been viewed more than 65 million times.
#3	Charlie Sheen	4	Actor Charlie Sheen gave interviews on a variety of TV & radio talk shows after the TV series Two & a Half Men ceased production. Users are ReTweeting messages from the real as well as fake CharIie Sheen accounts. They are also talking about Sheen’s Saturday night Ustream webcast.
#4	Soccer/Football	3	There was a lot of excitement over the unveiling of a new site for the the Sao Paulo Football Club. Barcelona’s French international defender Eric Abidal will undergo emergency surgery . Gilson Kleina will take over as interim coach of the Fluminense Football Club. There was also a friendly match between the USA & Argentina.
#5	U.K. Comic Relief	2	Red Nose Day is part of the UK Comic Relief campaign, an annual charity fundraiser held each March by the BBC. Funds are raised by a telethon and also by various “fun” events by celebrities, businesses and members of the public across the UK. It included Chris Moyles’ (of BBC Radio 1) attempt to set the record for the longest ever radio show, by broadcasting for 50 hours.
#6	Justin Bieber	2	March 1st was Justin Bieber’s 17th birthday and fans wished him a happy birthday. Beliebers celebrated the fact that their idol has finally reached 8 million followers.
#7	Harry Potter Movie Series	2	Harry Potter-related trends begin to trend when HP films are shown around the world, especially in Indonesia. There was also a debate between Harry Potter & Twilight fans on which book/movie series was superior.
#8	Carnival	2	Carnival was celebrated in many countries around the world but most trends are originating from Brazil. Carnival was marked by parties and parades sponsored by Samba schools which are broadcast on Brazilian TV.
#9	NCAA March Madness	2	Throughout the month of March 2011, college basketball fans Tweeted about teams they were following in the NCAA Basketball Tournament as they moved to the Final Four: Butler, UConn, UK and VCU..
#10	Lady GaGa	2	Several big events in March for Lady Gaga’s Little Monsters including her 25th birthday, the debut of the music video for “Born This Way”, and her Twitter account obtaining 9 million followers.

Image courtesy of iStockphoto, 123render

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