Everybody, everywhere has already established that "Terminator: Salvation" is a summer blockbuster flop; I just want to go delve a little deeper into its failings but also highlight the good points that (ironically) salvage the movie from itself.
I have appreciated Christian Bale in his roles ever since "Swing Kids" and "A Midsummer Night's Dream," but this is casting gone wrong. Despite the story revolving around Sam Worthington, Bale fails to convey the appropriate passion for the Resistance prepared for him by Edward Furlong and Nick Stahl, subsequently succumbing to the title conveyed upon Arnold Schwarznegger - just the action star. Featuring prominent actors in secondary roles (Helena Bonham Carter and Common) doesn't help either, as they inevitably draw attention away from the main characters.

The ultimate mistake McG makes is the failed cohesiveness of classic duality: action/story. If you're going to tackle a trilogy whose predecessors have action sequences that go beyond technology of its era, you need to create fight scenes that uphold that same expectation. The thrill of the Terminator series is the struggle to defeat one seemingly indestructible machine; here, McG creates hundreds that explode in as short a time as 15 seconds. (The much-hyped Ducati Hypermotard terminator is destroyed by running into an abandoned van.) The movie is indeed filmed as "gritty," but the end result is a realistic interpretation of fantasy. Moreover, "Terminator: Salvation" needs a fresh coat of paint - yes, Marcus Wright is the new human/machine prototype characteristic of each Terminator installment, but the T-800's lack any new features that would distinguish 1984 from 2009.
And the story itself seems forced upon audiences. Instead of taking movie-goers for a thrill ride, "Terminator: Salvation" makes people sit for two hours as McG shows them the origins of Kyle Reese without giving any of the characters' stories depth whatsoever. The mystery associated with each person goes unexplained in an unsatisfactory way - Marcus Wright's past lacks luster while Kyle Reese's history is nonexistent; Blair Williams' role is over-exaggerated and Kate Brewster's pregnancy is never remarked upon; and John Conner's imminent "false prophet" status goes over the heads of newcomers, as his innate knowledge and unnatural evasion of the enemy machines is unfounded. This is the consequence of concentrating too much on multiple characters.
Sam Worthington's performance is the only thing that gives the film its own salvation. Marcus Wright's soul comes from a genuine want/need for retribution - a "second chance" as he puts it - and the movie-made purpose for his existence is to underscore the apparent capacity as well as ironic duality of human compassion/machine calculation.
"Terminator: Salvation" was doomed from the start. I applaud McG for attempting to bring the story full-circle, but dealing with time travel while connecting the dots is a tricky lady. Hardly anything is explained: we still don't know how the machines target Sarah Connor, which still leaves us asking how Anton Yelchin goes back in time; it seems improbable (and nonsensical) for the machines to backtrack from a successful, emotional human prototype with the ability to infiltrate to an unmistakeably machine T-700 that stands out in the crowd; and, according to Christian Bale, the "war against the machines" is not yet over - so why are audiences promised salvation? The only solution I can think of would be the microchip wavelength revealed too quickly in the plotline; if this can control the machines, the mystery of the much-implied sequel has already been destroyed.