Why indeed! I enjoy Justin Long, (best known as the cute guy in the Mac commercials) but why recast the voices if they'll just be filtered anyway?
Matthew Gray Gubler (an actor best known as the cute young alterna-nerd in Criminal Minds on CBS) is barely known. And Jesse McCartney (star of long-cancelled Summerland show and teeny-pop star) as Theodore? It just reduces the characters I grew up watching on Saturday mornings.
This will not put me off seeing the film, but I am not happy about it. And just when I was getting excited that Rhythem and Hues of Golden Compass and next year's new Narnia film provided the CG effects.