If you want to create a vibrant culture of collaboration, you need to be OK with pictures of LOLCats, posts about the NFL playoffs, arguments about Apple and Android, and criticism of company policies.
Accept and embrace this fact now and your communities have a much better chance at succeeding. Or, continue thinking that things like this are a waste of a time and are unprofessional, and get ready to pay a lot of money for a system that ultimately no one uses unless they absolutely have to.
Unfortunately, "social" seems to have become almost a dirty word in the workplace, conjuring up images of employees whittling away their time on Facebook, talking to their boyfriend on the phone, or taking a three hour lunch break. Let's all agree now to stop trying to take the social out of social media. "Social" interactions not only needs to be OK, they need to be encouraged and rewarded.