This from an interesting interview with Feedburner on clickz.com:
Lessons from the Cutting Edge: RSS Advertising : One general theme from Feedburner’s testing will be of special interest to publishers: click-through rates from RSS feeds back to sites are decreasing. The company says this is happening across all the feeds it manages.
“If RSS popularity continues to increase, and it becomes less and less a vehicle for driving site traffic but more and more its own content-viewing medium, that presents an interesting situation to publishers,” Dick said.
Probably a more likely explanation is that people are adding more and more RSS feeds to their readers, but don’t have any more actual time to click through to full websites. So an individual site’s proportion of their attention is going down. But I think what Dick says about RSS becoming a “content-viewing medium” in its own right is really interesting. What’s the balance between keeping the “rapid read” capacity of RSS, and just mimicking the browser? In fact, what’s the point of RSS becoming just another web browser? And are we going to end up putting as much junk into RSS feeds as we’ve put onto websites, so something else comes along and replaces it with the original stripped-down purity of RSS?