Terminator 4 New Trailer

A new trailer of Terminator 4, the upcoming Terminator movie directed by McG and starring Christian Bale as John Connor:

In Terminator Salvation John Connor (Christian Bale) is going to meet Marcus Wright (Sam Worthington) who is some cyborg Terminator: is he a real friend or a foe waiting to strike a final blow on Mankind's resistance against Skynet?
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