This may be a silly question, but I'm curious. I don't currently have any AirPlay products, but I do have an iPhone 4 with the latest 4.2 iOS. When I load any music/videos/pictures on the iPhone, I don't have the little AirPlay icon (even grayed out).
Does it only show when you have an AirPlay product on the wifi network?
Does it only show when you have an AirPlay product on the wifi network?