The final part of your post was the best part.
As mentioned in the OP though, immersion is what the player allows, not what the game does. After only playing for 3 weeks I'm quite immersed in the gameplay in many ways. That's GAMEPLAY. I see the world, I understand it's aspects and much of it's lore along with the games gameplay and functionality to become immersed in it's totality, I do not try to seperate 'game' and 'world', since they both part of a complete package. The moment I sit down and decide to play the game for a few hours, whether it be leves or crafting, I am immersing myself in it, because I am focusing on it.
I agree with the 'game moving into beta' too, since the game is being rebuilt. Really what we are playing at the moment is part of the game as bits are being added, you could say the game is still in it's development phase even though it's live. And I think S.E are doing a good job, no game developer except them have ever attempted something like this before.
As for copy and paste enviroment I'll say what I said in a different thread.
I've ridden my motorbike through a lot of country roads that all look the same.
I shall go and complain to mother nature that she was copy&pasting.