Google have made a faq about their blog search available where they say:
There are a few different ways you can get to Blog Search:
* blogsearch.google.com (Google-style interface)
* search.blogger.com (Blogger-style interface)
* The Blogger Dashboard
* The Navbar on any Blog*Spot blog
It’s the same search in each place, no matter how you get to it. The Navbar, however, provides two buttons: one to search the blog you are currently viewing, and one to search all blogs.
This is a big move for Google and one which is long overdue – however they still have some work to do on it – I did a search for blog author “Tom Raftery” (vain or what?) and the most recent post I found was one written on the 12th of August! was This one of the last posts I wrote before I went on holidays for two weeks but I have been back now for over two weeks and Google’s blog Search appears to be blissfully unaware of this! Many people would say this is a good thing!
It does point to an underlying flaw somewhere in their algorithms though.
Google also allows for subscribing to blog searches similar to Technorati and other blog search engines:
At the bottom of each page of search results you can find several links, offering the top 10 or 100 results as either Atom or RSS feeds. Just grab the links from here and subscribe to them in the news aggregator of your choice and you will get updates whenever new posts are made that match your query.
Hat tip to Memeorandum