Bill Ives nicely summarizes the work that companies like IBM, Sun, Intel, SAP, and RightNow have done to develop their corporate social media policies:

• IBM Social Computing Guidelines
• Sun Guidelines on Public Discourse
• Intel Social Media Guidelines
• RightNow Social Web Employee Policy
• SAP Social Media Participation Guidelines 2009

Use inside the enterprise raises many adoption issues and they are no less important here. Some employee concerns can be clarified by a good set of guidelines. If done right these policies can actually encourage participation as employees are likely to feel more comfortable that their actions are sanctioned. They will also feel like they know the rules.