I REALLY hope Astrotrain will be in, but I doubt it - I haven't seen any clues to him being included.
Seibertron.com has pictures of the constructicon in the teaser
There's also a movie up on youtube.com with this figure.
As for the other characters in ROTF, who's gonna know???
There are rumours that Arcee will be a combiner of 3 motorcycles.
No picture of her combined has been posted as yet, but three motorcycles are seen in the teaser; also a pic of her (ugly!) semicombined state has been posted.