She's just being Miley?

So apparently someone wants America to wake up from environmental appathy and mindless consumption. And that person is none other that the tween mega-superstar Miley Cyrus. I wonder what effect this message has on the millions of tweenage girls all over America.

Is Miley Cyrus creating a new generation of green activites?
Was this whole videa her idea at all, or just some corporate PR scheme?
Does she really not understand what the terms 'global warming' and 'going green' mean?
How does this activism fit in with her heartland girl/Hollywood starlet branding?