Would be weird if all of a sudden every known DS games already made instantly become 3D if you play them on the 3DS. They would skip that initial lack of software support for it at launch. So mabe games designed specificly to look 3D will look that much better. But at first when everyone will be just seeing it for the first time, that feel of awe will not have settled in yet.
From a marketing pointe it would makes sense. Plus its not like making games for the DS will cost companies much money if the 3DS can already take old games and make them 3D looking.
This to me fits the Nintendo Glove. I can see them pulling somthing like this at E3.








