To me, Keanu has always been zen like in his acting. He's there and not there. I find that truly great!
This guy's been in at least 6 of my favorite movies since "River's Edge." A very underrated performer. I love how Zen and impenetrable he seems to be in real life and how that often comes through in his roles.
People say he's wooden, but I too feel it owes itself more to being rather than showing. Not completely deadpan nor Bressonian "model", but someplace in between.