Source (Crap the link was wrong. This is the link):
http://www.timesonline.co.uk/tol/news/world/asia/article2112763.ece
Excerpt:
A 6.8 magnitude quake, which shook Niigata on Monday and left thousands of homes uninhabitable, was three times more powerful than the designers of the nearest nuclear power plant – Kashiwazaki-Kariwa – had prepared for, or even imagined.
I'm sorta glad I don't live in Tokyo after reading this.
New panel to investigate Japan's quake-hit nuclear plant; report could be sent to UN
http://mdn.mainichi-msn.co.jp/national/news/20070724p2a00m0na010000c.html