So, a lot of people loved the book. These are not discerning readers, I am assuming. The book is a good adventure, but the voice is super annoying (whiny, teenage boy), though successful (at being whiny and teenage-y). What really sucks about the book is the "telling." Sentence after sentence we are TOLD how he feels, how he sees things, etc, and very rarely are we "shown" how he feels, etc. It is a long-standing, somewhat stale writing trope, this "show, don't tell" and one only really appreciates it when it is so frequently and obviously violated in a book that it just gets in the way of a good story. Beyond that, the writing is just not very tight or impressive, meandering into strangely constructed sentences, ineffective prose, and downright bad wording in some cases. So the book, in my humble opinion, is not very good. Those who loved it loved it because of the geekery and the nostalgia, not because it was a good piece of literature. Perhaps for a genre book, that's OK. (But really, readers, you need to hold the bar higher, to demand better writing...)
The movie is different. The plot is different. The road to the keys, in some cases, is even different. But I thought the differences from the book were good choices. They certainly did not detract from a good movie experience. A lot of the geekery was toned down, though I am sure if I were to watch at home with the ability to stop and rewind, I'd find tons of geekery stuffed in each shot in the film, too. Some of the special effects looked good (I'm no expert). The CGI was good as well. The dialog, reminiscent of the book, was awkward at times, and not just because it is supposed to be awkward teenagers talking. The evil corporation was underwhelming, more so than in the book.
Perhaps the biggest difference from the book was how the main character infiltrates the evil corporation. This happens in the book, and I had found it one of the more interesting events in the plot, but it does not happen in the film. I'm not sure why not.
Overall, if you didn't like the book, you might like the film. I thought the film was much better. If you loved the book because of all the geekery and fantastic trivia, and you're married to the books fantastic (uhm, cough cough) plot line, then you may hate the film. If you have not read the book (you aren't missing much, if you're a literature buff, but you should read it if you only enjoy genre fiction and are OK with plot-driven bad writing), then you'll probably find the film enjoyable.
The movie is different. The plot is different. The road to the keys, in some cases, is even different. But I thought the differences from the book were good choices. They certainly did not detract from a good movie experience. A lot of the geekery was toned down, though I am sure if I were to watch at home with the ability to stop and rewind, I'd find tons of geekery stuffed in each shot in the film, too. Some of the special effects looked good (I'm no expert). The CGI was good as well. The dialog, reminiscent of the book, was awkward at times, and not just because it is supposed to be awkward teenagers talking. The evil corporation was underwhelming, more so than in the book.
Perhaps the biggest difference from the book was how the main character infiltrates the evil corporation. This happens in the book, and I had found it one of the more interesting events in the plot, but it does not happen in the film. I'm not sure why not.
Overall, if you didn't like the book, you might like the film. I thought the film was much better. If you loved the book because of all the geekery and fantastic trivia, and you're married to the books fantastic (uhm, cough cough) plot line, then you may hate the film. If you have not read the book (you aren't missing much, if you're a literature buff, but you should read it if you only enjoy genre fiction and are OK with plot-driven bad writing), then you'll probably find the film enjoyable.