I liked very much that anime. The music act as a glue that makes it all come together tight. Something that the manga may lack. Not discrediting the manga at all. But watching her play those pieces by Bartok and Rachmaninoff is... oh mama. A delight! Also the music act as incidental soundtrack sometimes and fits marvelous. And her faces, she's super funny without being all exaggerated. But that's cuz she's so well written.
Oohhh you watched the anime! Yeah, the music is lacking in the manga version, sometimes after reading a chapter where they describe a song, I have to look for it and play it to know what they're talking about. Some anime interpretation leave a lot to be desired but I'm glad to know that it's not the case here :D.
It's really a great adaptation I suppose. I read a review from a guy I follow who's verymeticulous with his recommendations and critiques. And Nodame was with a well earned 9 in his perspective. I just can say that I enjoyed that anime in its entirety.