Well they actually went and changed that this generation because I remember reading that the gen IV logic would have resulted in ??? type. (People might have found out by hacking roost onto a converted Porygon or something. I don't quite remember) Anyway, I just had this weird lightbulb go off about Kyurem's move Glaciate. It's Frozen World in Japanese...like what happens to Unova in BW2. Part of me hopes it's buffed when carried by Black/White Kyurem or maybe it has some other battle or field effect now (accounting for the weird effect number in BW). Meh, guess we'll find out soon enough.