But how can it only be...???

Trailers, generally at least, are made from clips from the movie...occasionally those clips dont make the final cut and sometimes trailers are made that are origional in and of themselves...but looking at this trailer (and it really does look pretty dang cool) its obviously not a "created" trailer, but clips from the movie. So obviously there has been a lot of this movie created. Does anyone know if it WAS actually compeleted and just the legallities preventing it from any kind of release? i'd watch it...friggin producers. when did it stop being about the art form?