Mike Arrington of TechCrunch fame has a blog post entitled where he lays out the demographics of the various RSS readers used to subscribe to his feed. Below is an excerpt of his post and a partial screenshot of his FeedBurner statistics showing the top fourteen feed readers used to access the TechCrunch feed
Firefox (including Flock) accounts for 20% of feed readers. Bloglines is in second place with 13%, followed by NewsGator at 12%, Rojo at 8%, FeedReader at 7%, and Netvibes at 7%. Other notables include Pageflakes, Pluck and Attensa. If you add NetNewsWire to the core NewsGator stats, NewsGator is actually bigger than bloglines.
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The feed reader statistics are surprising to me both for the feed readers that show up in the list and for those that don't. For example, I'm surprised to see FeedReader at #5 yet not see FeedDemon in the top 14. Similarly, the popularity of AJAX home pages like Pageflakes and Netvibes over those from the big 3 (Google/Yahoo/Microsoft) is also unexpected. Of course, these statistics might be skewed because TechCrunch is one of the default feeds in Netvibes. A final surprise is that NewsGator Online is almost as popular as Bloglines among readers of TechCrunch.This seems to mean that the latter is finally getting a lot of cred among the early adopter crowd especially since the former has been slow to update in the past year.
For a completely different set of demographics, here are the top 14 feed readers used to access my RSS feed according to FeedBurner.
I wonder what conclusion you draw from how different the distribution of feed readers is in the above screenshots. For example, I think the fact that a bunch of Microsoft employees and developers on Microsoft's platfoms read my blog explains why there are multiple instances of feed readers based on the .NET Framework in the above list. In addition, I suspect this also explains why there is an entry for the Windows RSS platform in the top 10 applications hitting my feed.
On the flip side, I have no explanation for why it seems that NewsGator Online is half as popular as Bloglines among the readers of my blog.