It was meant to happen, Bayonetta's gameplay and difficulty appeals more to the hardcore gamer (plus the ps3 port kinda made a lot of people hate it) while Darksiders appeal more to the Casual gamer. And this Gen, casual gaming is the way to go -apparently- or just look at the wii's numbers.
Anyways. . i love Bayonetta and i don't need it to sell an amazing amount of copies, just enough so the developers keep doing games with a gameplay as awesome as this.