MSN Search introduced feed-specific search last week using two new search operators for advanced users: feed and hasfeed.
You may now restrict your search to only return results from the content of a RSS or Atom feed using the feed search operator. Here is an example MSN feed search for Niall Kennedy.
You may also restrict your search to only include HTML pages with a declared RSS or Atom link alternate. Here is an example MSN feed search for Niall Kennedy on pages with a RSS or an Atom feed.
These two operators pave the way for MSN to introduce search for users with the specific intent of discovering content sources for subscription. The value of feed-specific search for general content discovery depends on the total number of available feeds and the type of content they produced. We have search operators for specific filetypes such as images, PowerPoint, PDF, etc. but most people are looking at feed search as something new and revolutionary due to the emergence of a new content transport. MSN and Yahoo! will both show us their view of the world of feed search and allow me to reevaluate my thoughts soon enough.