Ever since podcasting got its big boost in May of 2005, I’ve been listening more and more to NPR’s “free” content.And less to everything else. NPR has wholeheartedly embraced podcasting, and I suspect that in spite of concerns from local stations, it was an easier choice for them to make than, let’s say, a media company encumbered by the need monetize the content.After all, I and many other NPR listeners still send in our pledges, even when all our content comes through a set of white earbuds.I think the NPR/iPod effect is one of the least reported and least understood aspects of the iTunes universe.I’m looking for the PBS/AppleTV effect to be just as important, if not more.Many commentators are asking if AppleTV is worth it. What counts as entertainment is different for different people, I suppose.For me, the fact that many PBS shows are available for free is very compelling. If PBS is willing and able to follow NPR’s lead in providing it’s content for free on iTunes, it could make a big impact on what gets watched on all the new AppleTVs soon to be deployed in livingrooms across the land.And it would probably have a big impact on PBS too.