They've been out for just over two weeks, but I think he means that D/P haven't left Japan yet.
I'd like a sequel, but not for a while. Again use it as a filler game between the actual Pokemon games. Plot wise it could be about a human turned Pokemon again, although altered, and it could focus on the Aruseus and perhaps Darkrai (it's presumed counterpart). Darkrai could be using the Aruseus plates to create armies of Pokemon so he can take over the world. You're enlisted to save the world by Aruseus, who is in a weakened state because he was seperated from his plates, but of course you don't know this at first. When you acquire all the type plates Aruseus reveals that Darkrai himself holds the last one, the ??? Plate. And thus you have to actually take on Darkrai.
Perhaps other legendaries could be included into the plot somehow, like Diaruga and Plakia could been enslaved by Darkrai. you could also perhaps have to assist Aruseus in building up a counter army, led by your own ranks and himself, but also getting assistance from other legendaries like Hiidoran and Regigigas and his Regibrothers.