Pretty okay.

Rating: 6/10 (7 June 2009)

I think it's worth watching, esp. if you liked the others in the series. You won't have Ahnold in it all that much(CGI cameo at end), you don't have Cameron directing it certainly, and you are always aware this is #4. But it works.
I liked Worthington though he is somewhat of a block of wood, still I rooted for the Marcus character and I liked what they did w/ him. The little deaf-mute black girl is just a prop and doesn't do much, but for whatever reason I wasn't bothered by her being there. I had to think hard to realize Bryce Howard Davies there was the Claire Danes character-they didn't give her all that much to do really.
Yelchin as Reese is very good, Bale mostly is one-note Johnny chewing the scenery, Ironside isn't on enough, you know. The F/X are quite good, the suspense of going into Skynet in SF and rescuing the prisoners tense and well handled, etc.
I'd say give it a 6.5 outta 10, **1/2 outta ****. You'll enjoy it for what it is.