Are you sure, they made DDR for gameboy color. So, theirs a 50/50 chance.more then likley DDR handheld will only bee for PSP, same with IIDX. because Bemani(beat simulation games by konami) where designed to run on a psx in the first place. any ways not hold your breath for DDR Advanced just yet.
DDR songs are different from original song. DDR songs are parts taken from original songs.KOE is lazy i can garentee that GBA will not see a DDR game, on a side note my DDR MAX style engine for the GBA is about half done. soon i should be able to play 1 DDR song with animations in a 8meg file so i might be able to get 3 songs on my cart