Conversation so far:
Is the Dark Roots of the Earth the name of an album by the band Testament?
Dark Roots of Earth is the tenth studio album by American thrash metal band Testament
Did many copies of the album Dark Roots of Earth by the band Testament sell?
Dark Roots of Earth sold over 20,000 copies in the United States in its first week of release. Around 60,000 copies in the U.S by March 2013.
How popular was the album Dark Roots of Earth by the band Testament?
Dark Roots of Earth reached number twelve on the Billboard 200—Testament's highest U.S. chart position to date.
Did the album Dark Roots of Earth by the band Testament stay on the charts long?

Question: What else is important about this album?
Self-contained rewrite: What else is important about the Testament's Dark Roots of Earth album besides copies sold, popularity, and chart history?