Basically, the claim made by Making Star Wars is that Episode VII concludes with a Shyamalan-esque twist in which the villain that's been butting heads with our heroes from the start to the film finally removes his hood and...
Dun dun dunnn...It's Luke Skywalker!
Many have argued that there can't be any truth to this rumor as George Lucas would throw a fit if the iconic hero he created decades ago was revealed to be evil in disguise all along.
Of course, the franchise isn't under Lucas' control anymore (Though he's still not a guy you wanna piss off.) and Luke going to the Dark Side would bring the story full-circle in a pretty satisfying way.
Frankly, we're just spitballing here, as like everyone else we have no clue what the hell's gonna happen in Episode VII.