I finally jumped on the T4 bandwagon after seeing the most recent trailer and now I'm ready to talk plot lines. But wait, this is all we get from Warner Brothers:

Set in post-apocalyptic 2018, John Connor is the man fated to lead the human resistance against Skynet and its army of Terminators. But the future Connor was raised to believe in is altered in part by the appearance of Marcus Wright, a stranger whose last memory is of being on death row. Connor must decide whether Marcus has been sent from the future, or rescued from the past. As Skynet prepares its final onslaught, Connor and Marcus both embark on an odyssey that takes them into the heart of Skynet’s operations, where they uncover the terrible secret behind the possible annihilation of mankind.

It's pretty vague, but if we read between the lines we may be able to infer some things.

Who is Marcus Wright?

Marcus thinks he is from the past, but the big reveal in the trailer obviously shows that Wright is indeed part machine. My theory is that Marcus is actually from the future of the future. Clearly Marcus is doesn't know what time he is in, in fact I believe that during the trailer he actually asks the question,"what year is this?" And even though he may believe he's from the past. There's no way that Skynet's tech was ever that advanced. So it stands to reason that Wright was possibly sent from the future of 2019. Perhaps he is the next evolution in Skynet's onslaught. They may have even sent him to compromise Conner's efforts. It's also possible he was reprogrammed sent by the resistance to help Conner, or as a sign of things to come. I don't think that this is unreasonable, because, after all, that's what John Conner did in the second movie. Either way good times ahead.

Cyborgs,Cyborgs,Cyborgs.

If Wright is truly as "human" as we see him be in the trailer, then this means that Skynet, at some point has developed an extreme amount of sophistication and finesse. But the question I have is about the other Terminators. For sure the T-800 will be in the movie, but what about the T-1000 and dare I say it, the Terminatrix? Were they developed after 2019? It makes sense if they were because Kyle Reese which places the movie somewhere before the inception of the the liquid metal Terminator. But why wouldn't the future Skynet just send the T-1000? I'm a bit confused about this one.

And what's up with Kate?

I thought that Terminator salvation was wiping the slate clean after T4. But why is Kate the physician/veterinarian in Salvation? She was a character introduced in T3 and payed by Claire Daines. This time around she's played by Bryce Dallas Howard. She was also said to have sent the model 101 back in time after it assassinated her husband, John Conner, in the future. She doesn't seem to have aged any since T3. I'm interested to see what role her character plays in Salvation. She's also carrying John's child. But I guess we'll have to wait on this one.

That's pretty much all I got for now, but I'm cooking up some other theories for another post. Until then...