GreasyDogMeat: After Avatar I have a hard time getting excited about the series returning to Cameron.
After Avatar and Titanic. God, that sucked. Anyway, he is likely to be busy with the next three Avatar movies long enough not to actually do anything about the Terminator in the next decade :P
And really, do we need more Terminator movies? I still think that the first one is best when considered on it's own, even though T2 is an awesome movie. I even like T3 more than most people (and I really love the ending), but that really was like the definite place to finally stop.