Well, ok, first impressions. Yes, there is a green tint, and most notably on the scenes that people have already pointed out above (the mountain shot with Boromir, the marshes with the Hobbits). One thing I don't get is that for some reason, in the marshes shot at least, it goes from green / cyan tint, to not, back again? Just one shot it doesn't seem to be there (the above tracking shot).
For me though, and this is just me, apart from the two blindingly obvious shots, if no-one had told me about the cyan tint, I would not have noticed it throughout the rest of the movie. I really wouldn't. That's not just bluster because I've bought the set, I genuinely would not have noticed. Fellowship is a primarily green / grey / blue tint all the way through anyway. I've always thought that Two Towers was mostly browns, reds. In that respect, to WHY they've done it, if it's deliberate, I think they are trying to give Fellowship it's own colour all the way through. More so than they had before.
If you're a purist, it will annoy you because you'll spot it because it's been highlighted. And it does seem strange they've done it in shots that were really crisp and clear, when Boromir picks up the ring, and it does give them a distracting colour. But honestly, hand on heart, I would not have even picked up on through the rest of the movie if I'd not read about it. It certainly doesn't show in a fair few scenes, and it doesn't in Rivendell.
Saying all that, picture quality is VASTLY better than the theatrical blurays. It really is. I tried a few scenes, Mines of Moria etc, and the detail really jumps put now. One bit I've always loved is the part where Aragorn allows Frodo to leave 'I would have gone with you to the end'. In THIS version, Aragorn's face, while grainy through the way it was shot, looks much more detailed than the theatrical bluray's. The detail in Moria, with the markings on the walls etc, is noticeably different. And the sound is immense. I usually have my surround on about 19 tops, which isn't too window shattering but loud enough. THIS I had to have on about 14, the DTS is fantastic.
So...
The cyan / green will annoy you if you let it in those scenes mentioned, but just flicking through I think it's a massive improvement on the theatrical blurays, and the picture and sound are excellent. The tint, to me anyway, isn't that noticeable throughout a lot of what I flicked through, but is there and more noticeable in certain scenes, but not in others. Not that much that it's a distraction except for that mountains scene and the marshes. Not enough to ruin it though.
EDIT - One last thing. As the above says, the blue / green tint does make other colours appear different, and if you want to see where, the scene where Gandalf drags Sam through the window. The very next cut is a dawn sunrise, pink sky and Gandalf and the Hobbits in silhoutte. On the DVD, it's a very rich pink, very colourful and deep. On these, it's very washed out, quite a lot actually, there is nowhere near the same level of colour. Which is a shame because that shot always looked great.
