Enterprise Social Software on the CIO agenda

With Microsoft buying Yammer for more than $1B, the growing interest to implement Facebook in the Enterprise is one of the hot topic when attending CIO conferences. After Atos buying the French Company BlueKiwi last month, to support their Zero email initiative, the market attractiveness is confirmed and large IT players who are trying to elevate their "Social Software" thought leadership will fight for the remaining players, at the same time SalesForce is moving all their customers to Chatter.
Who is next ? Jive , Socialtext , Telligent, NewsGator 
Forester estimation for Enterprise Social Software market is more than $6Billion by 2016, with a 61% CAGR !