Rough like written poorly. Card knew what he wanted to say in the story, so there's not a lot of pointless scenes, and the writing does bring you in. But if you stop to think about if the world actually makes sense, or the timeline of the story, or what the characters say from one chapter to the next, there's a lot of issues there.
I'm currently reading through a blog that goes through Ender's Game chapter-by-chapter, so that's why the issues with the book are very fresh in my mind.