This from the John Williams Fan Network, obviously take this all with a pinch off salt until confirmed by Bad Robot, Disney, Luasfilm or John Williams himself.
Following the rumor that the first teaser trailer for Star Wars: Episode VII will include original music written by John Williams, one of our sources claims that the Maestro will indeed record the new music next month in Los Angeles:
A reliable source just said JW received a trailer from JJ Abrams on Monday, Oct 20. JW has already written new Star Wars music to accompany this trailer. This new trailer music will feature new music and will be recorded on November 15 in LA with full orchestra. Still determining if the score will be recorded in London due to advanced age of composer/conductor. 14 hour flight to LA not too kind on 82 year old. This is all a secret and this message will be deleted shortly.
Will we be getting a trailer so soon? Time will tell...