In Sony's home country of Japan, the PlayStation Network isn't yet live. According to a report on Nikkei, Sony must first give "further information on what measures it has taken since an earlier hacking incident." This is all according to Kazushige Nobutani, the director of Media and Content Industry at the Ministry of Economy, Trade and Industry.
Nobutani points to two separate issues that must be solved by Sony before the PlayStation Network can go live in Japan once more. One is in regard to "preventive measures" that Sony hasn't yet taken as of May 13th. The second is a question as to "whether [Sony's security] measures are good enough when compared to countermeasures taken in the past."
There's no word on when either of these issues will be solved to the satisfaction of the Japanese government, and therefore no word on when PlayStation Network service will be restored in Japan. The PlayStation Network went live in much of the rest of the world this past weekend.