Recently went to the land of the rising sun. Megacorp jokes aside, I recommend everyone go at least once in their life. Beautiful place with a rich history and people aren't drek-heads. The Tokyo train/metro is a thing of beauty and efficiency once you figure it out.
Good for you. I used to love finding new places to see. Sadly, never had any interest in Japan when I was actually traveling, back when it was fun and easy. Now that I'm older, and travel is difficult and borderline unpleasant, I want to see it all, and probably won't. Did make it to Europe and the middle east, but not the far east. So unless I become one of the stupidly rich somehow, and manage a seagoing mega-yacht (on which you'd all be invited) I think that only domestic travel is my future; there's still a lot to see in the lower 48.