Google updated their blog search homepage. You can actually see the number of blogs that were posted about a certain topic. This can be helpful for SEO purposes as well to see what all the hype is in the blogesphere. According to a statement from the official Google Blog,
Today, we’re pleased to launch a new homepage for Google Blog Search so that you too can browse and discover the most interesting stories in the blogosphere. Adapting some of the technology pioneered by Google News, we’re now showing categories on the left side of the website and organizing the blog posts within those categories into clusters, which are groupings of posts about the same story or event. Grouping them in clusters lets you see the best posts on a story or get a variety of perspectives. When you look within a cluster, you’ll find a collection of the most interesting and recent posts on the topic, along with a timeline graph that shows you how the story is gaining momentum in the blogosphere.