Paul Walker & Vin Diesel Joining "Terminator 5"?

It's been rumored that Vin Diesel is once again up for the role as the new Terminator in Justin Lin's "Terminator 5". Paul Walker is also supposedly the number one guy for the role of Kyle Reese in the new film.
Lin said that he wanted the original films cast back, but it looks like he may want to go all "Star Trek" 2009 reboot on his film in the futuristic sci-fi action franchise. He's not ruling out on Arnie returning, but his life's up the shit right now.
Now seeing as Lin has directed both Diesel and Walker in the previous 3 or 4 "Fast & Furious" films, he most likely will cast them and will also probably cast most of the cast from those car racing films. He'll also have a few races in the new film too.