Ok, so this is a rumor this isn’t going to die until the 18th of December, but I’m going to throw in with my 2 cents. Luke Skywalker will not be evil in The Force Awakens and he is definitely not Kylo Ren.
Look I understand why these rumors started and why they are still persisting. But let’s be honest you know as much about Luke’s role in the new films as I do. I can only speculate on what I know. I think people are forgetting a lot of key facts when coming up with these theories.
I know what you are saying, but Luke turned evil in the novels. It’s well established that Luke turned to the Dark Side in the extended universe. But here’s the thing, none of that is cannon. Disney and Lucas film have officially announced none of what happened in the novels is cannon. That they are establishing what happened between Jedi and The Force Awakens in the comics Marvel is putting out now.
Sure it seems like dirty pool to erase all that stuff, but Lucas said it himself. He only allowed those books to be published, because he never intended to make any movies after episode 6. To him the story of Star Wars is the Story of Anakin/Darth Vader and the story ends with his death in Jedi. Now that Disney bought the rights that changed things, but they still say they aren’t cannon. So please forget everything from those novels they aren’t being used.
As for him being Kylo Ren that makes no sense. For one we all know Adam Driver has been cast in that role. In the recent trailer that is clearly Adam Driver's voice we hear when the show Kylo Ren. Plus there have been plenty of pics released with Driver on set in the Kylo Ren costume.
Some have suggested that this is all a smoke screen. They suggest this because us the whole Cumberbatch/Khan fiasco in the last Star Trek movie. But this going a lot farther and seems to be a lot more expensive just to keep one secret. So I call foul on this rumor.
Also there is the leaked photo of Mark Hamill. In the photo he is not wearing the traditional black of a sith, but white. And his outfit definitely looks traditional Jedi.
So then why all the mystery around Luke Skywalker? Well I think that's thanks to you internet. Some leaked plot details say that a big part of this movie is that Luke is "missing" and Han goes on a mission to find him. I believe that part of the story is they aren't sure what they will find, when they find Luke. So revealing he is good now ruins that suspense. Also by not revealing it creates more viral marketing for this movie then Disney could ever generate. So again we won't know for sure until December 18th, but this my opinion.
For more on my thoughts on The Force Awakens click here to listen to the latest episode of Super Hero Speak: