Keanu is also the interviewer and narrator. Don't let that put you off, this is a very good and interesting film. It's also well-balanced. There are plenty of old school folks who argue that film will always be better for various reasons, as well as a lot of other people who like digital a lot. The cast of interviewees is the a-list of directors and cinematographers in the current cinema, so there is a huge wealth of information here.
If you are at all interested in the differences and how filmmakers perceive them, this is worth the time invested.