Opens up the possibility for hackers to commit fraud and launch spam and virus attacks.
Increases the risk of people falling prey to online scams that seem genuine, resulting in data or identity theft.
May result in negative comments from employees about the company or potential legal consequences if employees use these sites to view objectionable, illicit or offensive material.
Potentially results in lost productivity, especially if employees are busy updating profiles, etc.
Employers do have the right to simply ban all computer activity that is not work-related, but this approach may not yield optimal results. If employees are to be allowed access to social networking platforms, then a comprehensive and well-defined policy should be established to prevent abuse.