Hey gang,
We have some good news from the Rock Band 4 front!
We're hard at work trying to make Rock Band 3 exportable into Rock Band 4 and are shooting to have that available with the December 8th feature update.
As a corollary, we are rapidly approaching the expiration of our ability to sell Rock Band 3. This means that you have until October 30th to buy Rock Band 3 from the Xbox Live® Marketplace or until traditional retailers run out of stock (if you're into that kind of thing).
So, if you are new to Rock Band 4, we strongly recommend picking up Rock Band 3! It's got a fantastic sound track that will be exportable. If you have already bought Rock Band 3, get ready to rock with all that great music in Rock Band 4. A few notes:
Don't forget - you can toggle between the new Rock Band 4 features and legacy features, like originally authored guitar solos, right in the middle of each track!
Best,
The Rock Band Team.