Yes, for the most part. The main differences are:
- Some songs have been added (we never had sheet music for Wipeout or the Walking Songs)
- Some songs are in the right key now (Blue and White and Hey Look Us Over were in the wrong key on the old sheet music)
- Most songs have multiple parts now (tuba and trombone parts were added, as well as harmonies and countermelodies)
If you already memorized all the "old" music, you can just keep playing that (unless you really want to learn all the harmonies, or you're a trombone or tuba player and want to learn the actual trombone and tuba parts).