NTF-Archive.de, the biggest German Transformers Movie news website, has posted the official German title for Transformers: Revenge of the Fallen:

Transformers - Die Rückkehr which translates to Transformers - The Return.

According to the German website, this news implies that the character "The Fallen" will not be in the movie, and that it probably means a character or characters from the first film will return.

Film writers for ROTF have already stated that "The Fallen" may not be in the film, but no confirmed reports have been released to date.

You may view the original article here, but you might prefer to read the translated version here.