We've done a few, and I've also done some feature re-recording, so I have some varied perspectives on it. In mastering it's not uncommon to add a bit of extra reverb for original soundtrack albums. The orchestral scores are designed for movie theaters which have a bit of their own room ambience, certainly more so than a living room; and the re-recording mixers can sometimes add some reverb in the mix, so what you hear in the theater may be wetter than what you receive in the mastering studio from the scoring mixer. We have a a t.c. 6000 which is wonderful for reverb, but for one score, we rented in a Lexicon 960 per request of the client. If you decide to add some to smooth things out and add some lushness, obviously you need to be careful and conservative in its application. Done properly, it can definitely make it sound more like a movie.