Sure, I'll believe that robots take over the world. That they are so smart, not only are they self-sustaining, but they are actually able to evolve. I'll buy that shit. I'll buy that they discover a way to make human tissue live on metal. No problem. I got all that. But hold the phone. Wait, what are those? What the hell are those things? White teeth? Okay, you just lost me. No credibility any more. Pack it up. You want me to swallow this, you gotta make those choppers nasty and chipped and barely hanging in there. Why would you drop millions upon millions of dollars to create robots that roam an apocalyptic world, but not drop a couple of dollars on some coal or something to dirty up everyone's teeth?
After watching Terminator Salvation, one can only deduce that in the future you have two priorities. Killing robots. And keeping them pearlies so white your friend or loved one can see themselves in them. To brush their teeth, of course.