Don't know why his line was cut from the trailer but he's been in for quite awhile now. I got absolutely lambasted when I said confirmation was coming in the trailer with his famous line(recorded again at his voice audition) of "Autobots, transform and roll out!" which was to originally end the trailer. They held out a little longer, don't know why. Welker is in too, don't know when that'll be announced. Most of the original voice cast has been approached if their characters appear in the movie. I know Dan Gilvezan has been approached to reprise Bumblebee.