As they said the skyrim world will be roughly the same size as cyrodil, I'm expecting an SI sized expansion for skyrim.
Any ideas what it could be? I would it to be High Rock, as it is just west of skyrim.

I always say the same answer in these threads so you can probably guess it.

Atmora

definatly high rock.

they'll have to cut 99.999% of daggerfall though..

Meh. For me, the real TES series started at morrowind.

The only problem with them taking us to High Rock is--- in TES, I can't help but feel like if I can go to a province, I should be able to explore it in full. That's just how TES works... So unless they were going to do ALL of High Rock, which would be ENORMOUS, I think it would feel weird to be confined to a small part of it.

Maybe Morrowinds mainland? (or whats left of it)

They're making one game per province, they're not going to slap on a complete other one as an expansion.