There are two twists to the story. Originally, when the service was launched, users only had to use temporary usernames and passwords to log in (http://joongangdaily.joins.com/article/view.asp?aid=2898718), but some time since December 2008 it was changed to full legal names and social security numbers.
Secondly, Google Korea just caused a big media stir in April by circumventing a new Korean government regulation that required any web portal which accepted user content (such as comments or videos) to ask for real names and registration numbers of all its users. Google Korea sidestepped this issue on its YouTube Korea site by disabling the ability for users on the Korean YouTube site from uploading content or posting comments. However, users could still access the international YouTube site without problems. This seemed to infuriate the KCC and caused them to start a 'legal review' of Google in order to try to nail them for some sort of violation as revenge. (http://english.hani.co.kr/arti/english_edition/e_editorial/350258.html)."
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