Considering that each and every region is connected to another one, this is a very plausible idea. Every region has an area that is impossible to get to. Like, North. No region as of yet has a northern area that is accessible. Could be that each region is connected to each other through this black hole of Northern areas, this meeting of the very large terrain. I'm assuming that north of every map is a large mountain, considering the terrain, but I could be all wrong about it. GF will have to explain this paradox sooner or later, considering their running out of ideas for pokemon.
I'm thinking a final edition? Pokemon RAINBOW VERSION!!!! Every region accessible!!! Probably not, since they want to milk this series for all its worth, but its a nice idea. to see all the regions connected and working, with storylines and quests to complete, all 32 badges, plus however many their will be in BW to obtain, maybe character customization... etc. But thats not my point. Its a nifty idea, but I don't see it happening any time soon. Nintendo thinks we're satisfied with HGSS.
And speaking of which, HgSs supports my theory. Perhaps that continent is connected to the Isshu, Hoenn and Sinnoh regions. Explained by Cynthia in the Sinjoh ruins, she says that the Johto and Sinnoh regions were connected and had a sharing of culture. perhaps this area is the center of all pokemon regions?
Perhaps we'll never know.