When you’re big, you’re big: Few bands ever debut in the top 10, and even fewer can do so with an album of B sides and throwaway cuts. But Smashing Pumpkins have pulled it off with Pisces Iscariot, which enters at No. 4 this week. After going a year and a half without releasing new material, headlining last summer’s Lollapalooza tour, and performing on the MTV Video Music Awards, the Pumpkins have clearly more than whetted the public’s appetite for new material. Awards, obviously, aren’t crucial to commercial success: Both the Pumpkins and this week’s other debut, Mary Chapin Carpenter, walked home empty-handed from the Video Music Awards and Country Music Awards shows, respectively.