In a situation like that? Probably not.

You said he buzzed you, how bad are we talking here?

Like everyone here, I've had people yell at me at one point or another. I usually let it go since the car is typically traveling much faster than I am. The only time I'll say something is if I catch them at a light, I usually try to kill people with kindness, but some people are just naturally agro for no reason other than the fact that I took a precious few seconds off their commute because they had to ease around me or don't think I belong on the road.

I've never experienced someone in a car targetting me and acting aggressively with their car (usually just verbal "GET THE F*CK OFF THE ROAD!"s), but if he buzzed you really bad, in a way that could have potentially wrecked you, or was swerving aggresively into your path of travel and then brake checking you, you should definitely report it. I've never been in a situation like that, but I would try to memorize the license plate and write it down or type it into my phone as soon as it happened, so I could report something more than just "a black car" or something vague like that.

If nothing else, after the report, he might get pulled over and the officer might question him about that incident, or at the very least (I would hope) show no leniency when it comes to ticketing. Maybe the person in question has a real hard on for cyclists and other cyclists have filed reports against the person, then maybe something would genuinely come of it other than, "We'll look into it."