So I thoroughly enjoyed most of the Ender series (both the main series and the Shadow series) regardless of the politics involved around Orson Card (let the record show that I don't much care for the guy as a human being).
I decided that, as much as I liked the books in the series, I didn't really want to see the movie, as I didn't think it would be possible to do the story onscreen without carving large chunks out of it, such as character development and probably all of the side story of Valentine and Peter... which is, sadly, almost exactly what ended up happening in the movie (I will not share how I managed to see the movie; suffice it to say that somewhere on the wide seas of the Internet, there may be certain hospitable harbors, one might call them bays, out there that sympathize with those of us less financially and morally blessed).
Now, I don't enjoy when a movie holds the viewer's hand; indeed, that's one of my biggest pet peeves in movies, TV shows, video games, and even in some books: sometimes, the audience is assumed to be idiots incapable of making connections and intuitive leaps for themselves.
So, upon viewing Ender's Game, I was elated that no effort was put into explaining what an ansible was or who the Hegemon or Strategos were. It was good world building in that the movie just throws these concepts out there without explaining them.
On the other hand, I was a little saddened that the side story of Valentine and Peter taking over most of the politics on Earth through their assumed identities as Demosthenes and Locke. I'm not usually one to lobby for splitting one story into two, but in this case, I feel that Ender's Game could have been better suited on all fronts by splitting it into two films and taking the time to focus on all of the aspects of Card's original novel.
The film itself is a beautifully faithful adaptation of the book; every small detail you could possibly want is in there, from the way the Battle Room looks and operates to the final confrontation above the Formics' home planet, it's a visually stunning spectacle with real weight behind it.
Speaking of the battles themselves, the Battle Room sequences are cut down to only two partial battles, which really stings, as it was one of the best parts of the book, but what really surprised me was, knowing the end of the story in advance and how the series went after that in the books, how emotionally affecting the final battle was. I found myself cringing as Petra brought the Little Doctor to bear on the Formics' planet. I felt dirty, almost. (As someone who has served in the military and has regretted being part of the invading force in Iraq every day since, the scene of the children staring out over the burning planet in horror particularly struck me; I had to take about a fifteen minute break before I could continue the movie.)
In the scene directly afterward, Graff tells Ender that winning is all that matters, and Ender replies, "No. The way we win matters," absolutely chilled me to the bones. Asa Butterfield is going to be a phenomenal actor in the years to come.
In the end, I'm glad that the movie was able to emotionally hit me like that; Card may not be the best person, and he may have a lot of bad writing habits, but he crafted a hell of a story perfectly translated to the medium of film.