The trailer was initially shown with the debut of Transformers movie.
Another which revealed the '1-18-08' movie name debuted with Beowulf (saw with my dad) officially titling the movie
Cloverfield
Even thought thats what people theoried the movie to be called since the transformers trailer
http://www.youtube.com/watch?v=ufYF0f-zMgY&feature=related
This is the new one.
http://en.wikipedia.org/wiki/Cloverfield