If you saw the new On-Location video at the official site, then you know at one point Ahmed Best holds up a call sheet for Episode II. Clearly visible at the top is a "J" in a font similar to that used for "Return of the Jedi".
This has lead many to believe that the title of Episode II could have "Jedi" in it.
Actually, what is more likely is that the "J" seen on the call sheet is the logo for "JAK Productions", the name Lucas uses for the prequel production companies. (Named after his kids Jett, Amanda, and Katie.) In fact, when Ahmed Best takes viewers into the office, he points out a JAK Productions sign on the door as seen below.
So you can probably be sure that there won't be a title released until the last possible moment (like on Episode I). Oh, and for a blast from the past, check out this old call sheet from Episode I which we posted in March 1998 from Bothan Spy. You'll note the JAK Productions title on top: page 1, page 2.