Saw it yesterday afternoon. Loved it! The plot did suffer a bit due to wandering and a few holes and such. All in all, I was happily surprised by the movie. Emotional in spots, brutal is some spots. A little comedy mixed in here and there to lighten things up.
I would say that if you have small kids, like below age 10, you should probably not take them because there are some really brutal things that happen during the course of the film. People being killed, robots being executed and torn apart in gruesome fashion and so on. The last 45 minutes or so is the destruction of downtown Chicago and just about everything you see. It's pretty intense and that may be a bit much for some younger minds to handle. The movie did earn it's PG-13 rating, most definitely.
All in all, it was an excellent movie. I would rate it a solid "B" for sure. The 3D effects were spectacular and worth the price of admission. I will probably go back and see it again.
"Ladies and gentlemen, take my advice. Pull down your pants... and slide on the ice." Sidney Friedman
"A hero is made in the moment, not from questioning the past or fearing what's to come."