In reply to:
I couldn't imagine anything worse than having that beautiful countryside spoiled by over-tourism. I hope they carefully remove the sets and put it all back the way it was, even the private lands.
Well, for public parks etc you are right - the land should be returned to the way it was [and it has been in general, as filming finished about 1 year ago now for all 3 movies].
For some sets [e.g. Hobbiton] there is a lot of interest from visitors already in seeing the site.
Having seen the actual "site" in its raw form [on TV rather than in person], the actual Hobbit holes and Hobbiton in general is quite small - only a small child would fit in the holes, so it would be a bit like visiting that world of minatures place up on the Canadian side of the border near Niagara [I visited there about 11 years ago].
I think longer term there will be a ongoing demand for visitors to follow some kind of LOTR film set trail throughout the country - and if you don't manage this properly [starting real soon now], then the unfettered public access to where people believe the LOTR sites were/are [whether te actual sites or not] will be more detrimental to the environment longer term than properly planned and managed film sets/locations.
This may be what New Line plan to do - I certianly hope they DO NOT buld ME-Land like a Middle Earth kind of DisneyLand - that would be crass.
And if they do, I hope its not built here