Mihai from the Google Reader team just posted some interesting data about observed namespaces across all feeds tracked in their system. The namespace data provides information not only about popular ways of expressing data, but also gives insight into blog software market share within a sample such as Google Reader subscriptions.
Dublin Core as the top namespace is not too surprising. What jumps out is the number of feeds using the default configuration on a variety of platforms, giving a glance into market share.
- Blogger – 12%
- FeedBurner – 4%
- Windows Live Spaces – 4%
- LiveJournal – 2.5%
Technorati and Google Calendar feeds appear to have equal subscription numbers among gReader users. Feedster and PubSub subscriptions each have about 1/4 of the popularity as Technorati.
Note: some sites such as MySpace declare the iTunes namespace even if their members never podcast.
Overall some pretty good data. Thanks for sharing Google!