It is an assumption but, until anything prooves differently, there is no reason to doubt that they weren't dubbed. American films subtitled are very very rare in Germany and France (next to none really), in Italy totally unheard of.

Films that you may find subtitled are some niche films from East Europe or Russia, but as long as it's American or European you may find the most unknown stuff dubbed for us, such as (off the top of my mind):

SilverWook said:

It also appears to be anamorphic, or does Youtube resize images to 16:9 on the fly now?

Don't think so, I have high hopes for this version. I can't wait

I tried to look for old reviews and for some reason I stumbled upon the New York Magazine ( http://www.google.com/search?q=thx-1138&hl=it&safe=off&tbs=bks:1,bkms:1168684103302643781&ei=xJD6TP7RGIqZOr6b7NQK&start=20&sa=N ) which wasn't too kind on it. However I found a later issue (1987) that describe THX as 1h28min long, so 88 minutes. Isn't that 2 mins longer than the original cut?

http://books.google.com/books?id=IeUCAAAAMBAJ&pg=PA69&dq=thx-1138&hl=it&ei=05D6TMj4KIPpOZaO5NQK&sa=X&oi=book_result&ct=result&resnum=6&ved=0CDsQ6AEwBTgU#v=onepage&q=thx-1138&f=false