As John Gruber noted in the Talk Show, the headphone jack on the 5th generation iPod Touch is approaching the edges of the device in a way that suggests it may soon limit how thin a device can get.
Bluetooth headphones aren’t mainstream yet, and until Apple makes my universal wireless headphones iPod Shuffle thingie we’ll need a temporary solution other than staving off device thickness.
Conspiracies of authenticator chips aside, the reason lightning cables have them is because lightning cables can do pretty much anything. The iPhone 5 (and everything else) can multiplex out any signal it wants based on what the authenticator chip tells it is plugged in. We already know that analog audio out is supported by the lightning to 30 pin adapter, so why not make a small dongle that just turns lightning into a female headphone jack? If they choose to go with a short cable rather than solid plug, making a quarter inch jack for studio headphones would be easier too, which could be a nice touch.
Again, this would be the cheap out-of-the-box solution. I wouldn’t be surprised if it shipped with said adapter pre-attached to the included earpods. The ideal solution would be the iPod Shuffle shaped device that pairs via bluetooth and turns any headphones into wireless headphones.