OMG have you seen Avatar yet?! The likelihood is that you have, as it is now officially the largest grossing movie of all time.
There is a great blog post over here (www.rifters.com) that discusses the scientific reality of the enviroment of Pandora, as well as some of the huge gaping plot holes that dent that credibility. From the sounds of it loads of money was put into researching and developing an authentic alien planet enviroment, much, much more so than into a decent script.
And here's something to make you really shudder - Twilight-meets-Avatar fan art. "Twivatar". Brrrrrrrrr.