IGN has several minutes of new gameplay footage of Castlevania: Order of Ecclesia, showing off new environments, new enemies, and new glyphs, which include a hammer, a giant scythe, and magical attacks like ice and fireballs. According to IGN, it's Koji Igarashi himself on the controls, playing his own game. Surprisingly, his playthrough looks like pretty much anyone else's -- Igarashi takes damage from normal enemies fairly regularly. Maybe he was just nervous with a bunch of IGN guys staring at him.
He also spoke in a video interview (available via the sidebar in that video player) in which he describes the premise behind Order of Ecclesia, including who the Order is and what Shanoa is doing invading the demon castle. While describing the differences between this and past Castlevanias, IGA also says that the animation of the enemies has improved. He must be referring to the ones that have new sprites!
IGA reveals the extra modes in Ecclesia: a hard mode accessible by completing the game, and a mode with a higher (255) level cap unlocked by beating that hard mode -- or by connecting Judgment on the Wii with Order of Ecclesia.