As the games have now REACHED the 4E, I think it's safe to say it will either happen in one of the next few games, or not happen at all, and I highly doubt it'll be anything less than the Main Quest of that entry.
I get the feeling that game 6 or, if it happens, 7, will focus on the Landfall. Which does excite me.
So, what do you imagine landfall would be like in-game, and how would you feel if the next game depicted it?
I imagine it'd be the Thalmor going through with their goal of DELETING [censored] EVERYTHING. Of course, that can't really... You know..... Allow for the games to continue......... So the protagonist will step in and stop them at the last minute.