You won't find a single, dominant player. In fact, some of the larger vendors have proven slower to adopt software "consumerization" practices....
Excerpt from the SAP: Jam evaluation:
"Jam is anemic when it comes to user profiles. The profiles are basic and the profile pages are neither rich nor engaging as they are in other tools such as tibbr...."(P. 234 in the Enterprise Collaboration & Social Software Report. )
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