I finally got to watch this, and I have to say, it's much better than I expected. When I had heard that the theme of the movie had been switched from mankind's capacity for nuclear annihilation to mankind's destroying the Earth through global warming, I didn't think it would work. But it did, and it felt really natural. Klaatu's line that"If the Earth dies, you die. If you die, the Earth survives. There are only a handful of planets in the cosmos that are capable of supporting complex life" totally tied it all together for me.
And I really liked that the "Earth Stood Still" moment comes at the end with no resolution. Yes, it throws mankind back to the bronze age, but it also gives us another chance to get it right this time.
And I did hear the "Klaatu Barada Nikto." It comes right after Klaatu has been shot and Gort starts to attack the army. And, just like in the original, it's the command for Gort to stand down. It was so distorted and mechanical sounding that the only part I made out for sure was "Klaat...Nikto," so I had to rewind it and put on the subtitles to make sure I was right; had I been in the theater, I wouldn't have been positive.
My only real complaint is that Klaatu didn't get to address the UN and make his speech, like he did at the end of the original. I suppose Jennifer Connelly, Micah, and John Cleese will get to relay his message to the world later, but it would have been better for mankind if they had heard from Klaatu themselves why they came so close to extinction.
Overall, I think I still prefer the orignal, but this was an enjoyable enough remake.