Well, I got this Idea while surfing around and well it should work. When Wotlk comes out just go to the area of the enemy faction where deathknights spawn and go on a killing spree ^^ they should have instant respawn rate because everybody and his momma are gonna start up a deathknight. I hope I posted this in the correct section. At least as long as blizzard keeps it's plans on how to make them available.