In the early days of blogging you could go to the Technorati Blog Index, enter some identifying terms for a particular niche topic and discover what the top blogs were in the field.

Identifying top niche blogs is invaluable knowledge for anyone wanting to enter, study or market to people in a particular field. It's one of the fastest and most effective ways to learn the lay of the land and get involved in the community of successful artists, real estate agents or 4-H club leaders using social media. I've been seeing a lot of demand for this information lately so I thought I'd write up some quick pros and cons of the options I'm familiar with. Perhaps you'll add some of your own favorite methods in comments.

Editor's note: Looking back over 2008, there were some posts on ReadWriteWeb that did not get the attention we felt they deserved - whether because of timing, competing news stories, etc. So in this end-of-year series, called Redux, we're resurrecting some of those hidden gems. This is one of them, we hope you enjoy (re)reading it!

Unfortunately, Technorati's not what it used to be anymore. While we here at RWW are very proud to have climbed to the #14 spot in the Top 100 most linked-to blogs overall in the Technorati Index (look out Perez Hilton, you're next in line) the fact of the matter is that for everyday use Technorati doesn't feel very reliable anymore.

How then can you identify the top blogs in a particular niche field? There are paid services you can use to identify influencers online but they are expensive and not appropriate for quick hits in a new topic. I'm all for paid services but in this case, let's talk about options that are fast and free. Given the need to classify a lot of content with minimal human intervention, this could be a great place for Semantic Web technology to come in.

Here's a comparison of the pros and cons of six different services you can use to do so. None are as solid a solution as the blogosphere deserves. This is a huge opportunity for indexes, but one that will be hard to fill since an index has to be wide and deep to be truly useful for this purpose.

Technorati

Pros:

The Technorati Blog Finder. was set up for just this purpose and in earlier days claiming and tagging your blog on Technorati was considered an essential step in getting started with a blog. I'm not so sure that's the case anymore.

Technorati offers a clear standard of authority and you can download the OPML file of the top 10 blogs in any category. Why only 10? I have no idea.

Cons:

After years of spotty service, seemingly random redesigns that made the site even worse than it was before, a crazy idea to get bloggers to point all their rel=tag links to Technorati (!) and the entry of bigger players into blog search - Technorati doesn't feel as active today as it once did. There are probably a lot of top blogs in any niche that haven't added themselves to the directory.

The directory is also organized according to the tags applied to a blog by its own author, typically when the blog just gets started.

The user experience is not good at Technorati but it's good enough to still warrant a look in hunting for top niche blogs.

Del.icio.us

Pros:

We wrote about how to find top niche blogs using Del.icio.us in a post last month. At the simplest level, go to http://del.icio.us/tag/topic+blog.

There's a huge amount of data on Del.icio.us and it's a very dynamic community. There are also RSS feeds, user comments, information about the people (users) who have done the classifying and a lot of other helpful features. I've been using Del.icio.us to find top niche blogs a lot lately and it's served me fairly well, even if I have to eyeball the last few yards to an answer.

Cons:

Del.ico.us hasn't been evolving very quickly, at least the publicly available version of the service. There are a lot of obnoxious qualities to it, like the fact that you can't search for most popular items with multiple tags - there's no such page as http://del.icio.us/popular/topic+blog.

Search results pages are funky and tag/topic+blog just means that a URL has been saved at least once with both of those terms, not that any number of people used both terms at once. It's not intuitive to look up the tags given a URL much less an entire domain. Finally, at least in the tech sector a lot of hip cats are using Ma.gnolia now instead of Del.icio.us. It's a recommendation engine waiting, forever, to happen and I'm still heartbroken that it was acquired by Yahoo! instead of the Library of Congress.

StumbleUpon

Pros:

StumbleUpon has huge user numbers, very targeted interests and classifications, and an algorithm combined with human editorial judgment about the blogs in question.

Cons:

It's more "fun" than it is business, unless you're into SEO. There's no clear way to look at top sites in any category. The search results page is really random-looking; good for stopping by and doing some searches just to see if you've missed anything, but nothing you'd do as part of a structured search.

Google Reader Recommendations

Pros:

Google Reader's new recommendations are very high quality, in tech at least, because they have a large number of web savvy users. I'm hoping that starting a dedicated Google Reader account filled only with some known feeds in a niche, I can have other top sources in that same niche recommended to me.

Cons:
Recommendations don't come right away, you have to wait for awhile. There's also a limit to the number of recommendations you can receive at one time. It is a tech-focused community, disproportionately to the blogosphere in general. Finally, this is a pretty silly little hack at things and you find yourself getting tied up with trying to run multiple Google accounts, etc.

AideRSS

Pros:

I love AideRSS because the criteria for hotness is relatively clear and I find the service really useful in lots of contexts. In theory you can plug almost any RSS feed, including search feeds, into AideRSS and it will score items in that feed for popularity based on number of comments, Diggs, del.icio.us saves and inbound links. You could put feeds from a blog search for niche-specific language into RSS and find some niche hotness. Once you identify top niche blogs you can also run their feeds through AideRSS to quickly discover what their communities of readers find most engaging. It's magic, almost.

Cons:

The service only works most of the time and long URLs choke it up. It's also limited to feeds, which take some creative thinking in order to bend to our particular purpose of finding top blogs.

Ask.com Blogsearch

Pros:

Ask has the best blog search on the web. It uses Bloglines subscription numbers as a big weight in spam control. There's very little spam. You can search for niche-specific language or a key niche link and sort by popularity of source.

Cons:
Ask does get overloaded sometimes and the above method is hardly systematic anyway. I wouldn't rely on it alone. Ask Blogsearch does index a lot of funky feeds that clutter search results even if they aren't spam. Try it out and you'll see what I mean.

Conclusion

See what I mean? Nobody quite does what we need. Used in concert and with a little work, these tools together can build you a pretty good reading list of top blogs in any niche. There's big room for improvement in this toolset though.

What do you use for this kind of research? I'd love to know.