Apple has announced that it has expanded its iTunes Plus offerings to over two million tracks, making the iTunes Plus catalog the “largest DRM-free catalog in the world”. Apple revealed the expansion, which includes artists from Sub Pop, Nettwerk, Beggars Group, IODA, The Orchard, and more, in a press release announcing new $0.99 pricing for all iTunes Plus tracks. “iTunes Plus has been incredibly popular with our customers and now…