20. A method comprising the acts: performing a digital watermark decoding or audio fingerprinting operation on received audio data to generate content identification data, said audio data representing samples of audio content for rendering into human-perceptible sound; identifying a first context factor of a first context class, said first context class being selected from the list consisting of (a) computing context; (b) user context; (c) physical context; (d) temporal context; and (e) historical information about any of (a)-(d); identifying a second context factor of a second context class, said second class being selected from said list and being different than the first context class; selecting software for rendering said audio data, based on circumstances including (i) the content identification data; (ii) the first context factor; and (iii) the second context factor; and rendering the received audio data to a user with said selected software; wherein at least one of said acts is performed using a mobile computing apparatus that includes a microphone and a camera.
20. A method comprising the acts: performing a digital watermark decoding or audio fingerprinting operation on received audio data to generate content identification data, said audio data representing samples of audio content for rendering into human-perceptible sound; identifying a first context factor of a first context class, said first context class being selected from the list consisting of (a) computing context; (b) user context; (c) physical context; (d) temporal context; and (e) historical information about any of (a)-(d); identifying a second context factor of a second context class, said second class being selected from said list and being different than the first context class; selecting software for rendering said audio data, based on circumstances including (i) the content identification data; (ii) the first context factor; and (iii) the second context factor; and rendering the received audio data to a user with said selected software; wherein at least one of said acts is performed using a mobile computing apparatus that includes a microphone and a camera. 31. The method of claim 20 that includes receiving said content using said microphone.