Yahoo! launched its blog search product tonight as a sub-property of Yahoo! News. Here is a results page on Yahoo! Blog Search for “Bush” for example. The content is also exposed on Yahoo! News Search result pages. Here is a results page on Yahoo! News search for “Bush” showing 4 results in the right sidebar.
Yahoo! branded the new search as “Blog search” but it is obvious from the results that Yahoo! is currently focused on one file format: RSS. Every search result in my test searches includes a link to the source RSS feed.
Yahoo! Search blog notes the index “contains content from a subset of blogs” but they would like to increase their index to include sources pinging blo.gs (currently tracking 9,730,011 blogs). My guess is the index contains content from the My Yahoo!, a source that is already well structured. News.com mentions the index currently includes only “hundreds of thousands of blogs” which seems really really small. Search Engine Watch confirms the index source is My Yahoo!.
The index seems limited to only recent posts. Searches for the last SuperBowl (SuperBowl XXXIX) returns only one result, and it’s from a site selling merchandise. Yahoo! might argue that as a news property blog search is only interested in timely data from the last month.
The search engine result pages (SERP) sort by “relevance” by default, applying Yahoo!’s secret sauce to bring popular items to the top. You can sort your results by date with an additional click.
Yahoo! RSS Search individual results include channel title, channel link, item title, channel title, publication date, and what appears to be a non-contextual excerpt. What’s non-contextual? Yahoo! quotes the beginning of the description instead of focusing your attention on the occurrence of your search term.
The SERPs include tagged photographs from Flickr on the right sidebar complete with the photograph’s title, thumbnail, and author.
The previously exposed alpha version of Yahoo! RSS Search included the ability to search by time, relevance, and popularity. The final version of Yahoo! RSS Search combines popularity and relevance into one sort function.
You can subscribe to any search as a RSS feed. Yahoo! promotes its own My Yahoo! property of course, but you can follow the link alternate or the orange-on-white XML button.
I am still digging deeper while attending the a mobile search event at Google. More later.