Dan Farber & Larry Dignan at ZD-Net have a good read on the race to "drop" social networking ways of working into legacy and legacy thinking sort of applications: Social networking: Quietly being subsumed by your everyday apps
Increasingly, social networking is looking like a feature more than a business. There will be big ramifications to consider as social networking becomes integrated into your everyday applications.
I don't think this strategy stands a ghost of a chance of succeeding. People who think that social networking is about "feature sets" are sorely misguided. It is way more about the culture and values that have been baked-in to these environments. Mess with the culture, and you break the conditions which give these applications their magic.
I've said it before, but I will say it again, what we see happening in the social networking space is more about values than software. If you don't understand the values inherent in these applications you are doomed to failure. It is obvious to me that the people trying to add these "features" to existing software haven't a clue what they are doing. The future is not a hybrid of the old and new-- it's completely different.
Trying to mix social-networking into a hierarchical command-and-control framework is like trying to mix oil and water. Mark my words-- these hybrid attempts are headed toward a colossal failure.