My 10 year old son is an EXTREMELY reluctant reader. This year at school they are required to read independently 30 minutes per day, so I loaned him this little illustrated book that I bought when I was 10 and the movie came out. He LOVED IT, and tells me it is the best book ever. I think that the following appealed to him: fast paced action, 3rd person perspective; the people matter but it didn't dwell overly on their feelings and emotions, fairly clear, simple language, interesting back story, not on earth (something uncommon).
I re read it imagining that I was my son, and I noticed that it was one thing after the next, nothing unnecessary. Certainly not the fleshed out character story that I like, but them I'm a 40+ reading woman not a 10 year old boy who dislikes reading.