Any content already made in RBN will be supported by RBN 2.0 in Rock Band 3. Using any of the new features will presumably make your content RB3-exclusive. Songs for RBN 2.0 will begin to release at the end of Q1 2011. Left out, however, is support for pro guitar authoring, as explained by Harmonix:
- The way that Pro Guitar DLC is implemented in Rock Band 3, it would have been substantial work to add to the pipeline for both Harmonix and Microsoft.
- It is extremely time consuming to author, to the point that it might be just as time consuming to author a Pro Guitar part as it would be to author the rest of the track.
- Peer Reviewing any Pro Guitar songs would be problematic due to the fact that we will be building a brand new install base of Pro Guitar players at launch.