Backing up what we were saying the other day, two hardcover graphic novels debuted on Publishers Weekly Bestseller list via BookScan. Superman Earth One, Volume 2 debuted at #18 with 4097 copies sold; the Avengers vs X-Men collection debuted at #21 with 3124 copies sold. Neither is likely to stick around on the charts for too long—although Superman could be a sleeper—but they are definitely respectable debuts.