It's been suggested in other topics that revisiting other lands outside Skyrim proper may be a possibility. So let's get some solid discussion here on the pros and cons, and likelihood.

The game is called "Skyrim", but in 200 years what Skyrim is could be vastly different from what we knew in the closing years of the Third Era. The warlike, expansionist Nords may have incorporated unexpected lands into their province.

In Oblivion, rumours state that the Nords are at war in Solstheim and Morrowind. I doubt we'd visit the wasted island of Vvardenfell, and the Velothi mountains provide a natural barrier in gameplay terms to stop the player venturing eastwards towards Blacklight. However, I'd love for us to be able to revisit Solstheim - seeing how the Dunmer refugees and Skaal get along, what remains of Fort Frostmoth and Raven Rock (likely ruins - RR is already bust by Oblivion, and the Nords at that time are 'attempting to recapture the whole of Solstheim, and remove the Imperial fort from the island' - the crippled Empire likely couldn't hold out long). It's likely that Solstheim - long disputed territory between Skyrim, Morrowind and the Imperials - has finally fallen to the Nords and become part of Skyrim proper, with the latter two of those powers out for the count.

Given that Skyrim is said to have varied climates and terrain types, its possible parts of what were Hammerfell/High Rock are now part of Skyrim, similar to how Cyrodiil snagged the Trans-Niben from Elswyre.

It'd be interesting to see what's happened to Bruma in the past two centuries, seeing a weathered statue of the Champion of Cyrodiil and the snow-choked remains of the Great Gate. Although, as with the Morrowind border, the Jeralls are a natural barrier - plus they'd have to figure out how to stop us wandering down into Cyrodiil. Glimpsing White Gold Tower and being unable to get there would be torture - in previous TES, views of the lands outside the star province are less than stellar. Endless sea in Morrowind, generic countryside, mountains, forest and swamp fill in for views across the border in Oblivion - no landmarks in sight.

However, this is all just wishful thinking - having the province of Skyrim, detailed, will be enough for most gamers I imagine.