Chernobyl was an old and simply unsafe reactor that due to its really poor design created a major disaster that has had ramifications for decades.
Japan's issue is more like 3 mile island in US. Its a FAR better design that has numerous safety precautions and like the 3mi island issue, it won't have long term effects beyond the cost of rebuilding replacements.
It had no major health issues and withing a relatively short period of time clean up was completed.
Japan's reactors are more advanced than that and will be contained with no major human health issues.
I'm against nuclear power. I'm convinced that radioactive waste will cause severe problems in the future. My opinion on this matter won't change as long as i live. At the same time I'm absolutely aware that my opinion on this matter won't change anything. Nuclear power plants existed before I was born, they will exist when I'm not around anymore. Radioactive waste will contninue to be buried around the world. I'm not interested in any links which should show me that nuclear event x was not as severe as event y and should be compared to event z instead. No discussion needed.