I've been keen on using social media for marketing and supporting gaming communities. On our site for Aion I added a feature to the backend CMS to enable the community guys to auto-tweet whenever they post to their official blog. We decided to experiment with the feeds being game+language specific so that we could maintain the service if a community representative moved jobs aion_en, aion_de,aion_fr. The feeds have worked quite well and the community reps are tweeting in addition to the article autotweets, which is great because otherwise they are just glorified RSS feeds.
The possible problem starts when company member's personal Twitter feeds are publisised. I think that people realise that blogs are personal and do not represent the company, but maybe it's not so clear that games company employees have a public face and a private face. Obviously, everyone who publishes any information into the outside world has to keep in mind that it can be read by anyone, but Twitter is just so quick and personal.
So, should we insist that company members keep their Twitter feeds private? or maybe just remind everyone that they need to be responsible in what they say, exactly as if they were blogging?
UPDATE: I forgot to mention that Jen looked into this a fair bit and included a clause in the company handbook that specifically covers employee conduct in all social spaces. Some people end up having two accounts which they use for their public and private personas.