The Constitutional Court has ruled the online real name system unconstitutional:

As the AP reports, the law was introduced with the intention of reducing incidences of libel, false rumors and abusive comments. However, the Constitutional Court today said that there was no evidence that it had achieved those goals, and that a mandatory real-name policy undermines free speech and discourages people from voicing opinions for fear of punishment.

The law had proved unpopular in the country, and was easily circumvented. As AFP notes, many Internet users began using non-Korean services in order to continue using false IDs online. Google was among the supporters of this loophole. In 2009, it was reported that the Korean version of YouTube had uploading and commenting features removed, actively prompting users to log in to another country’s version of the service in order to get involved.

Probably a good thing, even if on a private level I’d strongly consider implementing a real-name system in my comment section if I could.