Arbitron is currently testing the Portable People Meter in Houston.
For years the radio industry has been rated using a paper diary system to figure out who was listening. A bad estimate system that has so much against it, there is very little good to report.
The PPM, however, is something that seems to make so much sense to me. Stations encode an inaudible signal that then a pager-sized unit "listens" for. There is still the problem that the sample from the public is likely a poor representation of the population. But, in terms of actual monitoring of what people are exposed to, the PPM is a HUGE step ahead.
Of course, when you change the way you record listening, things change. Check out this article (with special thanks to my friend Sam Bradley at Ohio State---click to his blog--Comm and Cognition)
It is also interesting to wait and see how Arbitron's PPM move will play out in the future. Of course, with Hurican Rita appropriately interrupting the business concerns of the test, Arbitron may need to do even more testing before rolling this out nationwide. Plus, they are still claiming publicly to be interested in joining forces with Nielsen because of how expensive the technology is. But, the PPM technology does not really seem to need Nielsen's blessing to record television signals as well. If Nielsen doesn't agree to come on board permanently soon, could it be that we'll have some actual COMPETITION in the audience measurement system?