For what it's worth I've just been reading the latest issue of EDGE. It has a PS4 versus Durango feature and they discuss the leek
http://www.vgleaks.com/world-exclusive-durango-unveiled-2/ with a developer working with both machines. They confirm the leeks as correct although EDGE is careful to say that the GPU is from an unknown vendor but freely state the cpu as the Jaguar. Further when questioning the developer further he readily admits that the PS4 is the more powerful machine but the differences are marginal, like that from the 360 and PS3 he states. By the way it's St. David’s day and I'm Welsh so leeks is spelt correctly
Basically what EDGE is reporting are the leaks seen regarding Durango are essentially the real thing and I wouldn't expect anything different come it’s unveiling.