FF-XIII.net reporter Maiki has written summaries of both the Final Fantasy Versus XIII and Final Fantasy XIII trailers from the Jump Festa. These were written in English and not translated via google unlike earlier misleading reports.
Final Fantasy XIII
-Music was a slow peaceful string-centric orchestral piece
-Very pale-skinned lady in a white flowy dress and feathery hair played a huge harp on a watery surface
-In a dark space, a floating object spewed out a bunch of CD-like discs all over the place and Pigtails Girl picked one
-Later you see a small creature with white body but greeny face summoned (out of the disc?) and the girl smiled at it
The article continues with Versus as well as features artwork draw from seeing the characters in the trailers.