I review films myself on Amazon. I didn't review this one simply because 200 people beat me to it. But I like the review you have written; far easier to read than some of the others. I also agree with your point about McG. There was nothing wrong with his work as a director at all, and I as well have not seen a better futuristic war movie outside of the future war segments from the other Terminator movies. And yes, the enormous Collector robot was very impressive. The bile thrown at McG seems to result from the realisation (as you quite rightly put it) that he is not James Cameron.
The only issue I do have is with the material which has been quite noticeably cut from the film. There are certain scenes in the final film which abruptly jump from one scene to the next without the filler scenes that you normally get to balance the pacing. This was obviously to ensure a shorter running time enabling the picture to be screened more times a day so as to make back on the huge $200 million investment. One example of a cut scene was the capturing of the hydrobot. One moment Kate Connor is discussing the idea - and the next they have one in their hands already back inside their camp! There are other examples that McG has also drawn attention to, informing us there was roughly 30 minutes taken out of his original cut. The Blu Ray has 2 more minutes or so added but I would very much like to see the longer cut. Just how likely this is with the rights to the Terminator franchise resting in the hands of something known as 'The Pacificor Hedgefund' I cannot say. They part-financed the operations of the Halcyon company who produced the film, then promptly bought the rights when Halcyon went bankrupt after the movie didn't deliver the stratospheric box-office they hoped for.
Just one tip about your reviews. Try not to give away plot-spoilers. After I received negative comments from other reviewers and 'Reported Abuse' to Amazon, Amazon promptly deleted my reviews (without sanctioning the critics) for giving too much away. It doesn't matter now as Salvation has been and gone, but in future you might want to hold back some clues so as not to spoil things for those who have not seen a movie when you have reviewed it.