We decided to watch this film on Blu-ray yesterday evening as a pleasant way to finish our day out. It's an enjoyable movie, but it really could have been (considerably) better. The film itself and its special effects are pretty good. I’d say the special effects are very well done. The airships look fantastic. The design successfully evokes the retro feel of the book without seeming ridiculous. I do think they made the green men too thin, though; I've always imagined them as much larger and more frightening. I like Woola’s appearance, even if his movements at “supersonic” speeds seem a little excessive. Still, it seems that every film studio or production team now believes they can take an old classic, put its name in the title, and then do whatever they want with the source material. This movie has taken the basic concept and character names from Edgar Rice Burroughs’ John Carter book but deviates significantly beyond that. At most, 10% of the story from the books made it into the film; the rest is completely original content, and it doesn't enhance the narrative. In fact, it transforms what was a good story into typical, uninspired Hollywood fare—I’ve seen it all before. There are numerous examples: the white apes that are the size of dinosaurs, the city of Zodanga moving around (what on earth?), most of the plot as I mentioned earlier is fabricated, and the Therns have an entirely different function, and so on. I particularly dislike how they’ve portrayed John Carter, the honorable gentleman from Virginia, as a fairly ordinary American guy who initially resists doing what's right. And those flashbacks involving his wife and child? Those are just unsettling. These changes don’t make the movie any better. It received 6 stars; it could have earned 9 or 10 if it had stayed true to the books. Disney is responsible for this film being a disappointment at the box office, they messed with classic material…again.

Source on TMDB