It's Epic, has miniature proportions.
Originally titled The Leaf Men, and based on William Joyce's book, Epic is an upcoming animated adventure film from Blue Sky, the makers of the Ice Age films and Rio. This trailer plays like a cross between The Guardians of Ga'Hoole and Avatar (by which I almost mean Ferngully), with a bit of Disney-styled "comedy animal" side business.
I like the look of that rather a lot. It should seem particularly dynamic in 3D, and the rendering of nature is certainly quite pretty.
Though the overall focus of the thing seems to put the focus on the wee soldier, that last scene seems to indicate that our protagonist is going to be a miniaturised human girl. Perhaps that was her dad in the Rick Moranis suit at the beginning?
Amanda Seyfried, Colin Farrell, Josh Hutcherson and Beyonce Knowles are amongst the voice cast.