Well, without reading too much of the topic, I finally received my copy yesterday and have progressed nicely within the game (I think I just completed about a third of the game).
Initial thoughts are unsurpring:
Absolutely speechless about what Naughty Dog have achieved. They've been one of my most admired developers since the PSone days and still continue to do so. The graphics, smoothness and art-direction are outstanding. The gameplay mechanics are definately a step up from Uncharted 1 too.
Despite all this, I still don't enjoy the shooting as much as I do the platforming, adventuring and exploring, but that's down to personal preference. I'm playing it on normal and even on that, the AI is very good and quite a challenge in some parts. They don't stay in places and if you stay in one place too long, they'll tackle you from the side, making it even more difficult. I also like the new focus on the stealth elements, making it possible to sneak up to enemies and knock them out without alerting the huge battle.
Only little annoyance is that I have, is that if you're once in the battle - no matter how well you hide from your enemies out of sight, they still remain aware of your position and usually your change of position. It would have been nice if you were able to lose them again and keep them guessing while cooling down the action a bit.