"twice as much potential value lies in using social tools to enhance communication, knowledge sharing, and collaboration within and across enterprises."
They also suggest that productivity of interaction can be raised by 20-25 percent. I am not surprised, and agree that the potential is definitely there. Still too many silos in organizations that inhibit effective communication, knowledge sharing and innovation across (especially larger and distributed organizations). The report does mentions that the cultural effects play a key role as well.
And that is where a danger in falling short lies. Social Media tools externally seem to be "just there". To treat them the very same way internally will miss a lot of the potential, just like many "KM projects" in the past missed their potential value marks. To make the potential come true it needs more than just a tool, it needs a full-fledged initiative with the right support infrastructures (sorry, yes that means some investment in people as well - no free lunch). The tools must be simply to use, available anywhere anytime, if possible integrated into other information channels, but that alone is not enough.
You also need to create the type of support roles that are needed to cover community management, marketing and (business) training. "Build it and they'll come" is likely to fall short on the benefits. But with some investments into those support infrastructures it is a lot more likely that the potential benefits actually materialize.
Social Collaboration is a big trend - but as many trends make sure to not just pick one element (the tools) from it and forget about the rest. With the proper community management, marketing the business benefits properly to platform members and training them on their information channel portfolio management you have a much better chance that those involving will find it a useful tool for getting knowledge-work done.
If you like to learn more about how get that "support" piece working, the upcoming book "Connecting Organizational Silos" (pre-order now, available in Oct 2012) can help you.