Susan, I may have missed your use case, but the answer is that it really depends on the use case, goals, charter, leadership, sponsorship and a myriad of other factors.
I recently had a demo of the SuccessFactors products as was underwhelmed with their 'view' of 'community'.  Jobs2Web is how they view the world through this aquisition.  The Bill and Melinda Gates Foundation is their main customer who are helping them to 'define' their community requirements at this point.
 
Not sure what you are trying to accomplish with newsgator, but certainly I like the notion of 'weaving' the social listening platforms together to foster social learning.  I believe the bridging is the next big actvity we will start to see in the next 18 months.
 
Kind Regards,

Lauren B. Klein,

Community Consultant and Coach

748 S Meadows Pkwy
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