Had they not turned into Metalligrunge, maybe Metallica would have given Maiden a run, but it's not the case. Maiden has had a longer run, more classic albums, and i think, puts on a much better live show.
The second trailer was released.
http://www.youtube.com/watch?v=9cTPLVkEWic&eurl=http://wewerethecoolkids.blogspot.com/2007/11/cloverfield-how-it-all-went-down.html
Right around the 1:09 time mark, there seems to be a silhouette of something "attacking" a person. Haven't pulled much else out...