Batman vs Superman: Dawn of Justice Trailer Leak
You can view the trailer here via TheVerge.com:
The picture quality isn't great and the sound is decent, but you still get the sense of what this movie is about. There have been rumors since the official announcement of Batman vs Superman that a good portion of the film will be loosely based on Frank Miller's The Dark Knight Returns. After watching the first trailer, you realize quickly that Snyder went heavily in this direction, full with the armored Batsuit.
All I can say is, the trailer builds, builds, then builds until you see them face off. Get your popcorn ready!