The Story behind the founding of Cyworld - one of the pioneer virtual world social networks

They are ranked 500 or so of all websites.

I presented Sleep.FM - The Social Alarm Clock at TechCrunch40 where a VC spoke of this, as http://www.sleep.fm is a virtual world social network too. I thought Sleep.FM was the first virtual world like social network. Interesting to learn otherwise. Also, another investor informed me of Hive7.

Well at least Sleep.FM is the first Social Alarm Clock :) . So far haven't been told otherwise!