Yes, I have seen it. I'll post a review in a day or so. It was quite good.
I am not certain why it was released earlier in the UK and elsewhere. Perhaps they wanted to build buzz for the film (knowing it would be huge in the UK, where they love bond even more than they do here). Perhaps it was merely a matter of the US release schedule being more crowded and this date working best for them. It may also have been a calculation to have the film still be relevant and in moviegoer's minds over the Thanksgiving week, which is a big one for movies.
-Jason "Skyfall is certainly among the 10 best Bond films but I think it comes up a tad short of the top few" Evans