I concur. Honestly, under other circumstances, it's impossible for Vanitas to come back since he was obliterated in the end of BBS. Since we're dealing with Nomura here, he'll most likely set up some sort of paradox that somehow brings him back (maleficent for example), since he's probably in high demand. Haha I personally want a Sora-Vanitas showdown in the next game. It's gonna be epicc x)
I agree Nomura somehow in one way or another he's going to bring back Vanitas and of course the X-Blade will come too after all it plays and important role to the series...and yes a Sora-Vanitas showdown totally awesome.