Other than the plethora of folks dressed as Jedi or Death Maul, there wasn't much of a Star Wars presence at Comic-Con, as it looks like Disney may be holding of any major casting announcements for Star Wars: Episode VII until D23 in August. That would certainly make sense for the Mouse House, but it's possible that their plans may have broken early, if the latest "scoop" from Latino Review is to be believed.
The site, which has a pretty sketchy track record in my opinion, has an inside source who says that Disney is eying Ryan Gosling and Zac Efron for the next Star Wars film, which is currently in pre-production in the UK. Gosling would apparently be in line to play the son of Luke Skywalker in a story set thirty years after Return of the Jedi. Efron's role is less clear, but the recently confirmed casting announcements have parts that would seem to fit both actors reasonably well. Screenwriter Michael Arndt is expected to deliver a totally original approach, so looking towards the novels for clues is probably the wrong way to go. We'll hopefully learn more soon as Star Wars Celebration is this weekend, and filming should begin early in 2014.
In a related story that Latino Review puts out there as if it doesn't matter, they say that not only was Leonardo DiCaprio approached for a Star Wars role, but he turned it down in favor of joining the live-action Robotech film. Based on the classic anime series that spawned a thousand imitators, Robotech takes place in a future when humans have gained advanced technology from a crashed alien spacecraft. Movement on the film has been slow, and last we heard it was unknown Nic Mathieu called on to direct it. Who knows if that's still the plan or if things have changed along the way. If they're looking at stars the caliber of DiCaprio, it seems unlikely that a mostly untested director would be in charge.
Both of these stories are shaky at best, and it should probably be noted that the site seems to be jumping in front of any bad press by shouting "EXPECT DENIALS FROM ABRAMS". But assuming any of this turns out to be true, would you want to see Ryan Gosling or Zac Efron in Star Wars?
