Praise the superhero Gods: the official trailer for 'The Avengers' has arrived -- and it does not disappoint. After all the hoopla and magazine previews and Comic-Con panels, we finally get a substantial look at a film that was first teased three years ago at the end of 'Iron Man.' The trailer doesn't offer a whole lot in terms of story -- other than that lots of stuff is blowing up in New York and the Avengers need to save everybody. Another thing the trailer doesn't tell us: who the bad guys are. Yes Loki, is the main villain, but he definitely is getting some help from another group. We assume director Joss Whedon and Marvel want to keep their identities a secret as long as possible.