Hoenn and Unova would be a pretty sweet combination. Unova has very little explorable water and Hoenn has way too much. Together, the game would have a nice selection of environments.
Also, in many ways GS was RBY 2. It was a direct sequel. At Advance generation the series kind of rebooted. Players were unable to catch any old favorites until the FRLG remakes.
So here's what I think now: if they're calling these games BW2 we're probably talking about a significant update. There will be new Pokemon apart from the Kyurem formes.
What is the primary reason for releasing two versions anyway, isn't it for version exclusive Pokemon? There's typically a single third game because all the current generation's Pokemon would have been available between the first two anyway. There can't be true version exclusives without Pokemon unobtainable anywhere else. Heck, Platinum, a single game, gave us five Rotom-A, Shaymin-S and Giratina-O which are all essentially new Pokemon. Yet all we know of so far from two games is the two Kyurem formes. It seems reasonable that there will be more.
My expectation is that we'll get new formes or evolutions of existing Pokemon rather than new concepts altogether. Especially in Hoenn (lol), there are a lot of weak Pokemon that could use an evolution or forme change and we didn't get any of that in BW. So I suddently have rather ambitious expectations. But after thinking about it, two new games based on the current generation don't seem to be worth the trouble (extra packaging and shit) otherwise. There has to be enough new stuff to justify it. Most people will only buy one anyway, esp. if they're essentially the same as BW.
