We just pushed an update to the SDN search, which included greatly enhanced search within Sitecore Community Blogs, and integrated SDN Forum. Now you should be able to search against any Sitecore resource from one place!
Among other enhancements, we’ve improved search relevancy by tweaking a few settings and ignoring landing pages.
Hope you see the difference.
Feel free to provide feedback, especially if your own blog is not getting indexed by us.
Enjoy!