Japan earthquake search results lead to malware
It's a common way to trick users into installing malicious programs like fake antivirus or fake system maintenance tools. By getting in quickly on new search terms as the become popular, malware pushers can get their "poisoned" websites into the top positions on sites like Google and Bing. That puts the searching masses at great risk, even if it's only a short amount of time before such sites are filtered.
The best protection is to be aware and click only on results from trusted sources for news in cases like this. If you've never heard of a site pushing Japan earthquake news in your search results, it's a good idea to steer clear.