"I could use Facebook to do
something seriously - but I cannot use Sharepoint to do something fun."
Koch 2008: 423
But there is an even more fundamental message in the quote: Social Software is built for being a 'medium', i.e. being flexible to be used in different settings for different - not yet envisioned - tasks, while CSCW tools are too much focused on the task, leaving users too little freedom. Sharepoint can only be used (easily) for one particular thing - coordinating access to documents and exchanging information in teams in forethought ways. However, Facebook (or any combination of Social Software like blogs or wikis) provides a quite generic communication platform that can be used for the tasks Sharepoint can, but also for others.
Koch 2008: 424
See (google) also my Term "Verwendungsoffenheit" and the closely related "Nutzungsoffenheit" by Richter and Riemer.
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