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Facebook's list of 40 most shared articles of 2011 is quite revealing. Among the stories most shared -- Ryan Dunn Dead: 'Jackass' Star Dies In Car Crash, by The Huffington Post. REUTERS

Facebook has increased the upper limit on the number of characters allowed for status updates. The exact count, as of now, is 63,206.

The limit on the number of characters has been expanding almost as rapidly as the social networking Web site itself. Until March 2009, the limit was barely larger than Twitter's, at 160 characters. That month the company increased the limit to 420 characters. The company then pushed it to 500 in July and then made it 5,000 in September.

Twitter, on the other hand, has a limit of 140 characters. However, Facebook doesn't let its users go on for as long as Google+, where the limit appears to be 100,000 characters.

It seems that Facebook is doing all it can to maintain its dominant position in the social networking segment. This year, Facebook rolled out scores of new features and updates for users' profiles.