Soon Twitter and Facebook became popular services that looked and worked much like them emerged to meet the demand for closed private social messaging. Status.net (formerly Laconica), for example, is a Twitter clone while Yammer provides a Facebook-like experience in a private setting. Glassdoor appears to provide a closed audience take on Google+ Circles. The difference is that while Google+'s Circles is one-way (only the Circle creator knows who is in a Circle), members of a Glassdoor "Boards" [...]

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