So, what's next for Pokemon. R/S remakes? Head straight for 6th Gen?

But it never mentioned when B/W takes place, as far as I remember.
Just cause B/W comes after Gen 4 doesn't mean it comes after in the time line. See: Gen 2 -> 3

For all we know, B/W takes place before every other game and that could easily set up for an appearance by N.

Actually we do know it takes place long after the other games.

If you transfer a Pokemon from FR/LG -> DPPT -> BW it says "After a long travel through time..." or something to that effect.