This is an image ripped from the copies of the cloverfield trailer that are circulating youtube/liveleak that precede the film beowulf, this is a quick glimpse of something massive moving behind a building. it doesnt really dispel the rumours that it is godzilla with the shape being very dinosaur like but hey who knows what it could be, as one poster on imdb said it looks kinda like a kangaroo with a messed up face