The Binding of Isaac creator (and co-creator of Super Meat Boy) Edmund McMillen has detailed the game's first and last DLC expansion, "Wrath of the Lamb." It'll add about 50% more content to the game, he said on Formspring, while on Twitter he revealed it would cost $3 and be released "when it's done."
The Binding of Isaac is a parable of sorts, harking back to that old Bible story while at the same time being a game mainly about poop. Your main weapon is a child's never-ending stream of tears. It's punishingly difficult, and you lose all upgrades, items and progress when you die. If that sounds up your alley, we highly recommend it.
Have you got a chance to try it out yet? Would you be interested in some DLC? What about a 3DS version? Let us know in the comments or on Twitter.