I think it is a good concept, but I doubt that Apple would do it without introducing something more interesting to an iPhone GB version.
This post on iLounge claims that iPods running OSX could be announced as early as September. I have to say that if they are as limited in terms of their scope as the iPhone, I don’t think their going to do much for me!
It seems now that this forum thread about the GBA / DS emulator for Palm may not get to the DS part for some time after all. A bit of a shame, but you never know, it still may deliver in the end.