BioWare recently told The Game Reviews that they have DLC planned for up to the next two years for Dragon Age: Origins. Executive Producer Mark Darrah said the content will likely be "item packs" and "larger quests that might last an hour or two, up to even fully fledged expansion packs."
He went on to say that the content should make it onto all platforms, though pricing is mum as of now. We’ll see if BioWare can produce on this comment. They said roughly the same thing about Mass Effect, but the game only received two DLC packs.