Harmonix has warned that some downloadable tracks may disappear from the Rock Band store as long-standing license agreements expire, with some Metallica tracks already pulled.
As is common to most music licensing agreements, many of Rock Band's DLC licenses have fixed terms. As the franchise is now five years old, some of the earliest licenses are coming to the end of their lifetimes.
"Our Music Team has been hard at work extending these licenses to make sure that this has as small an impact on the community as possible, but there may be a very limited number of songs that will no longer be offered for new purchases in the Rock Band store," Harmonix warned on the Rock Band Facebook page.
Metallica Pack 01, as well as individual tracks Ride The Lightning, And Justice For All, and Blackened have all been pulled from the Rock Band store and will be removed from the Nintendo Network, PlayStation Store and Xbox Live Marketplace shortly, after which they'll no longer be available for purchase. These offerings released on November 20, 2007.
"We’ll post as more information becomes available, with relicensing updates likely coming in on a quarterly basis. We’re hard at work to minimize the impact on the RB catalog and RB community, securing extensions for an overwhelming majority of content and, most importantly, making it a priority to give you advance notice if songs are expiring and have to come down. We’ll do our best to make sure that you have one last chance to buy these legacy catalog tracks," Harmonix said.
Happily, this doesn't mean the DLC you already own is at risk, and Harmonix does not foresee any issues re-downloading legacy tracks, either.
Harmonix officially ended DLC support for the Rock Band franchise last week, which kind of broke my heart.