Talking of Infinity Radio, the Viacom radio division has said it has stopped its station managers from "doing business" with independent radio promoters. Their announcement follows similar moves made by rival groups Clear Channel and Cox Radio, and is an attempt to demonstrate once and for all that they don't accept money from record labels to play music on their stations.
Payola, while certainly not as widespread as in the past, is of concern again because New York Attorney General Eliot Spitzer is investigating whether record labels use independent promotion companies, who buy data off radio stations, as a way of buying airtime for their music on the sly.
The move does not stop radio stations dealing with independent promoters (ie being plugged music by them), but, in theory at least, stops any payment channels between promoters and stations which could be used to conceal payola.