While I strongly support free speech and believe security researchers should be given some extra latitude when appropriate, what I saw was not at all appropriate. I saw two well respected security researchers sitting in a room like Beavis and Butthead laughing and remotely disabling a vehicle on a multi-lane interstate highway, like it was a big joke. The reporter in the Jeep literally says "This is dangerous" and asks urgently for help. This all filmed and posted to Wired for the world to see, like they are proud of it.
Before working with computers I drove tractor-trailers for a while and was lucky to achieve a million-mile safe driving award. I have a pretty good idea of the dangers here and I know that stretch of road well, I've crossed it many times. I know from experience that a car stopped in the middle of a multi-lane interstate is one of the most dangerous situations you can be in. I've had people hit me who didn't see my huge trailer with flashers on and warning triangles out on a sunny day - it happens quite often. I've seen dozens of people killed in situations exactly like this. You see it coming and a random driver just plows into the stopped vehicle.
I exercised my judgement and decided to phone the local Highway Patrol office. I've read the negative comments and I disagree, I still think it was the correct thing to do. If you are a researcher and you do something this dangerous, and are foolish enough to then post it on a high-traffic site like Wired, I think you forfeit any right to a discreet warning and you deserve to have the police show up demanding answers to some tough questions.
[1] http://www.zdnet.com/article/google-outed-me/