Below is a chart of 5-year credit default swap prices for Japanese sovereign debt. As shown, there has been a small increase in default risk in the days since the devastating earthquake and tsunami hit, but default risk is still below levels it was at in May 2010 and February 2009.
At the moment, it costs $95 per year to insure $10,000 worth of Japanese sovereign debt for five years. As shown in the table of CDS prices below, Japan remains at the low end of default risk compared to other countries around the globe. With the resilient country fighting to get back on track, investors don't appear to be worried about Japan having financial problems.