Most of Japan is perfectly fine. And the cherry trees are still blooming in Tokyo, same as ever. People are just not entirely sure it's alright to be celebrating this year when there is so much sadness going on by Tohoku. It's a cultural thing ... by not celebrating and sharing in the solemnity, you're showing support.
Tokyo is mostly fine, it'd be the cultural sites by Tohoku that you'd need to check on. If you can think of a place, you can look it up on wiki and see where it is. That ought to answer any questions you have on it. Wiki's good for giving locations. I don't think there's much famous in Tohoku though. Certainly, nothing as famous for beauty as Hokkaido or Kansai. Kyoto's untouched. I live there and I can affirm that from walking around every day.
In most of Japan life goes on as normal.