If I report intentional dangerous driving to police, will it have any effect?
I'm convinced that the prevalence of cameras is changing the attitude of certain drivers. 

For the last year or so, I've ridden with a helmet cam. I'm now on my second camera and I'm toying with mounting my old camera (lower definition, poorer lens) on the seat post to face to the rear. 

It wasn't for this kind of situation, but it would certainly be useful as evidence. If you search YouTube there are many, many examples of similar behaviour. If the police can't or won't help, just publish the footage on the web - the driver will almost certainly never see it, but you never know. 

I've had several situations where a rant from an angry driver has suddenly become an embarrassed silence when I've pointed out that they're being recorded and I'd be quite happy to post the results to YouTube, the police, their employers (this does work well if it's a work van or similar) ... 

There have been several cases here in the UK where dangerous and aggressive driving has been prosecuted successfully solely on the basis of the cyclist's camera evidence. 

On the civil side, I know personally of one accident victim who was knocked off his bike and whose claim was enormously aided by the footage from a cyclist behind them who had been wearing a camera. Anecdotal, I know, but he is certain that the claim was processed more smoothly because of the video recording.

If this seems like a good idea, the answers to what-is-a-good-camera-arrangement-for-city-riding or recommendations-for-inconspicuous-helmet-mounted-video-camera might be useful in finding an appropriate camera solution.

In the first case, though, I would definitely contact your local law enforcement agency. You never know, maybe this miscreant has done it before. If a handful of independent people all report them, there's an increasing chance of something being done. And you're raising awareness in the police that there are people willing to stand up and complain. 

It might also be worth talking to your local councilor - ask about what they might consider doing to make life safer for their electorate ...