Every man and his dog seem to be running a blog nowadays, and for good reason. Blogs are a great way to get your message out and indexed almost immediately, which will help drive potential traffic to your website (for more information about the importance of blogs, check out this article). Yet, because countless blogs are shot into the blogsphere everyday, every minute, every second, there are miles and miles of towering piles out there that can be difficult to sift through to find the good nuggets amongst the bad. This means there’s an obvious necessity for blog search engines that return relevant results. However, like the regular search engines, not every blog search engine is created equally. Some are better than others at providing the results you’re looking for.

Along comes Sphere to compete with quality blog search sites like Technorati. Sphere promises to return very relevant blog searches based on three key algorithm functions that work off of the keywords you enter into the search bar. These functions include:

Link structure
Relevance is weighted by who is linking to whom. Sphere examines relevant links between bloggers based on the search terms, and gives precedence to blogs containing links from the most authoritative sources. The greater the amount of relevant links, and the higher the quality of links, the better the ranking the blog receives within returned results.

Semantic analysis
Algorithms examine the content itself for relevancy, distinguishing subject matter based on authority. Sphere does not use tags.

Meta data
Sphere builds a profile with metadata for every blog it examines, and returns a title and abstract showing frequency of posts, average words per post and all inbound and outbound links.

Sphere seems to be fairly intuitive and easy to use, which is nice. The page layout is simple and not overly cluttered, with a number of interesting features. You can display posts by relevance (spam is placed at the very bottom of the list) or time. You can select a custom date range from a drop down menu, which works between one hour and four months. You also have access to a standard search (‘Blog Search Results’), a ‘Featured Blogs’ search related to your keywords, and a ‘Related Media’ list, which contains news, podcastas, photographs, and book links based on your search terms.

There’s also a sphere it tool for download that lets you find blogs related to the web page content you are currently viewing. This tool works best on pages containing one specific topic.