One can spend quite a lot of time searching the listed blogs. I looked at the top 100 blogs (by authority) list and subscribed to a few (have to weed my list at Bloglines). Then did a search for learning 2.0 using the Quick search option with a result of 7,471 sites. After a quick look at the first two pages it looked like there are a lot of irrelevant sites on the list. I did the same search using the tags option (in advanced search) and got a result list of 623 sites. After a quick look at the first two pages I found that more of the sites on this list were relevant, though there were some duplication. So, the tag search may be a better option than the keyword search to start off with.
To compare the results with other blog search engines, I used Google Blog search (result = 200,021 sites) and Bloglines (result = 95,500 sites). Both these search engines came up with an overwhelming number of sites. Looking at the first page I didn't see any overlaps with Technorati, though Google blog search and Bloglines did have some of the same sites listed on their first pages of results.
It might be a good idea to use Technorati and Google/Bloglines when searching for blogs. When using Google or Bloglines a narrower defined search should be used to get more relevant results.
A pleasant surprise was that you could subscribe to your search query in Technorati. Now that has great possibilities for research, picking up trends or staying up to date.
