Wouldn't be surprised if the 3rd movie was bad. 2nd one was very unsatisfying. It didn't feel like it stood very well on its own, and it felt like the majority of the movie was spent explaining the whole "cannon" concept.
Every scene dragged on forever past it's point. It was aggravating to watch compared to the first movie. And then bam, it just ends out of nowhere. They could have cut a ton of time out of it with better editing.