15 Minutes of Content
I'm already thinking about how I can restructure many of my courses to smaller 15 minute bites.

I see the connection between the attention span and this sound bite era. Could it be that the advertisers picked up on this human ability and are making the most of it? But, by providing the students new information in 15 minute packets of time, I think allows time to absorb and process the new information. I like trying to give a summary, ask questions and have a discussion after about 15 minute of lecture.
There can be no doubt that in the era of soundbites in which we exist, the general attention span has declined significantly.