I saw this yesterday, and absolutely loved it. I went with a fellow music major, and we spent a lot of time exclaiming in surprise at the great use of so many classical pieces (when was the last time I hear Mozart's clarinet concerto at the movies, even if they totally skipped playing more than 3 measures of the clarinet itself?) - and my God, the way they used the 2nd movement of Beethoven's 7th was just... so perfect. That's my favorite symphony and I was just beyond emotionally moved in that moment.
The whole thing was just great though, music geekery aside. Firth was absolutely amazing. The whole cast was pitch-perfect. I hope this wins some big awards soon