What I mean is that DLNA seems to be always used in the context of "I am here, and my media is over there". For example, I have music or movies stored on a remote server or a NAS, and I want to bring it into the device I'm currently sitting at (a TV, an iPod or iPad, a PS3, another computer).
Whereas AirPlay seems to be the opposite: "My media is here, but I want to play it over there". You use AirPlay to redirect the audio/video output from your iPhone or iPad or computer to a remote A/V device like your stereo receiver or Apple TV.