I fished the book and watched the movie. I really enjoyed the book and have started Ender's Shadow. I'm enjoying that as well so far.
That said, I really didn't think too highly of the movie but not because it was particularly bad or anything. I feel like they did a good job with what they had but that there just wasn't enough time to get into the details they needed. It's obviously difficult to condense the contents of a novel into a feature length film and some are more successful than others. In this case, they just weren't able to get enough content in to really give the feeling of the pressure put on Ender to push him right to the edge of his abilities.
They basically touched on each of the scenarios he went through to get to the end but without the serious conflicts faced in each. Without that, it all just seemed too straight forward.
I don't know whether it should have been split into multiple films or whether it just can't be filmed at all. I guess it just is what it is.