More story titles are revealed in Steven Moffat's Production Notes column in this month's issue of Doctor Who Magazine.
Episodes 4 and 5, the first two-parter of the season, are The Time of Angels and Flesh And Stone. This story features the return of both the mysterious River Song and the Weeping Angels.
Episode 6 is titled Vampires In Venice and is written by Toby Whithouse.
These are working titles and may yet be changed prior to transmission.