It is, and yes, I'm not sure how well Bethesda will handle that. ESO did give us some new Khajiti lore which wasn't entirely terrible, and could figure into a game plot quite easily...but I'm not sure how well Bethesda will handle a non-human, non-mer centered game. Personally I think Valenwood would've been boring, possibly after spending hours grinding my way through those zones in ESO and wanting to die every step of the way, but between the well established lore, the lack of VA issues and the potential for a Thalmor-Empire proxy war, it seemed like an obvious option. Same for Hammerfell, only even more so.
It's also possible I'm completely wrong. I shied away from it being Summerset Isle because of the mountains and arid landscape, but a lot can change in a thousand years, and Summerset was hit hard by the Oblivion Crisis. Equally, it could be the coast of Valenwood...but I think if it were they would focus far more heavily on the forest theme. I mean, the game's Valenwood, so gotta show the woods themselves, right? Hammerfell...eh, if it was the Craglorn region, maybe, as there are some quite fertile areas around there, it does actually strongly remind me of the region around Dragonstar, but it's landlocked. Doesn't look at all like High Rock, I very much doubt they'd go back to Morrowind...it could maybe be Black Marsh, as we don't really see the coastal regions of it in ESO, only the northern region of Stormhold, on the Morrowind border.
Or maybe they're actually going to break with tradition and do something genuinely new with TESVI. Yokuda, Atmora, Thras...Akavir? I highly doubt it, but anything's possible.
So yeah, my guesses in order of preference are Elseweyr, Black Marsh and Valenwood. One thing they did say is that they were waiting for the technology to make certain things possible that they wanted to do with TESVI, which I think had everyone thinking Valenwood (walking tree cities). But maybe they wanted it for something else.
