The music is very Italian influenced, almost operatic at times. And the story... well, it's Fellini. I think it's a very well-executed melodramatic musical.

Here's a clip from when Antonio Banderas did Guido's first song from Nine at the Tonys. I didn't care too much for Banderas' performance, but it gives you a great idea of what you're gonna be looking at.

http://www.youtube.com/watch?v=mZDxvSU13vo