I have been researching a bit on social media in public organisations, and they often tell sad tale of no traffic wastelands. There is so much crap content on the web, that users quickly skip through anything that does not catches on immediately. Pointing back to what you said about communication departments, then there is a second challenge in producing content – or facilitating content – that both co-workers and visitors would actually engage in. And for that, I think you are right, that people with communication skills need to be closer to the action.