Some of the acting is quite good. Bale, Sam Worthington, and especially Anton Yelchin do some great work for a summer movie. However, Common, on the other hand, dude, maybe you were inspired to act poorly because your last CD, the aptly titled "Universal Mind Control" was weak in itself. I'm a fan of Common, but dude can't act.
But what's with all this ACTing talk, what really matters is the ACTION, and boy does the film deliver. There many sequences here that are well directed and just totally badass. I haven't seen a film with this many explosions since, damn, I can't remember, Pearl Harbor?. The price of the gasoline used to create these fireballs probably drove the national gas price up.
After the film ended, I left tremendously satisfied. This is popcorn summer action goodness at it's finest. Sure "Star Trek" is a better all around movie, but "Salvation" delivers better and more "Ohhhh Shit" moments. Oh yeah before I forgot, Arnold does appear, and he rules, and it's not really a cameo. The theatre went bananas when he appeared, which is funny cause he's still the Governor. Guess it's just part of thislalife.