You should try InWorldz. It doesn't use a HMD yet (though there has been some work done on a true VR client), and the graphics quality and physics may or may not be as perfect as you want, but it fits what you are looking for exactly in the social aspects. There is no 'game' per se, other than whatever contests, roleplay etc. that users might choose. Some people do spend most of their waking hours socializing there, or running real businesses there, etc. All the content is created by users.

https://www.youtube.com/watch?v=w4KvpOrSNLU