All I want is unique environments, and no more generic field, forest, mountain. Give me fjords, give me frozen lakes, give me fertile valleys, show me the taiga. Show me Nordic cities, not just castles. Let me see inspiring Nordic culture!
I mostly don't give a crap about what kind of environment they are going to pick; my concerns are all about a world with some [censored] interaction in it, a world which doesn't feel as empty and monotone as Oblivion did.
Yeah, it's fine if it looks good, but it's far more important if it feels true, rich, detailed, coherent.
If we are going to see once again beautiful landscapes with just some random autoscaling monsters wandering around, you can paint me disappointed.
I want to see caves with hidden treasures and some powerfull monster watching them, cliffs to climb, places hard to find and rewarding to explore, dungeons which are big, unique and scary, with traps which are actually dangerous and must be avoided (look at Vindictus beta) and so on.
In this sense I think Gothic saga has often delivered more compelling worlds than TES, in the past.