Jay Feinberg articulated much better than I did in my previous post, what the implications of slidecasting are. He tried to post this as a comment, but turns out my commenting system was broken.
“One comment about the web and audio: there is a standard, or, at least, emerging standard, way to connect together multiple segments of audio: the playlist (and the XSPF standard playlist format). And, a slideshow seems very similar to a playlist in the way that you have discreet elements stiched together to form a linear presentation.
From a music / arts perspective, I would imagine that the most interesting possibilities would be the most web-like, e.g., that any one slide could connect to any playlist of multiple audio tracks, any one audio track could connect with any presentation of multiple sides, or one audio track could just connect with one side.