In the social media world, Facebook is always scrutinised closely. The last two weeks, though, have brought more buzz than usual, according to new research from Meltwater Buzz.

The company's expansion plans, coupled with continuing concerns over privacy, contributed to fluctuating sentiment, as illustrated by the infographic below. Facebook CEO Mark Zuckerberg's account was hacked, and pictures posted online, revealing a security flaw that attracted criticism. 

Meanwhile, Facebook also acquired location network Gowalla and announced plans for a major new office in New York.