Does anybody know what the requirements are for The Elder Scrolls Online?

They haven't posted them yet but it shouldn't be too much of a problem. They've at least said they want several hundred people to be able to render on screen, so the requirements might be fairly minimal to accommodate more players.

There are several threads about it. We know nothing.

But if you're asking for some guess: If GW2 doesn't run, likely TES:O won't either.

https://en.support.guildwars2.com/app/answers/detail/a_id/1119/session/L3RpbWUvMTM1ODg0MDg5OS9zaWQva2lQaDVXZ2w%3D

Developers said they are wanting the game to run on systems that are 5 years old.

running =/= playable