Yesterday Yahoo! Site Explorer decided to retire from business. It has left many amateur SEOs, and some professional SEOs too, at a bit of a loss. Many SEOs and agencies have been using the back link service in Yahoo! Site Explorer to monitor, analyse, and generally try to copy the link building actions of their competitors.
As someone who has been involved in SEO for over 5 years (not so much by choice but by necessity) I have used Yahoo! extensively, and seen my competitors use it against me, too! I manage several sites across various niches, and some of my sites do interlink with each other, wherever a connection really does benefit a reader. I have seen people leave comments on all my blogs, and doing so in the order of Yahoo! backlinks for my main website.

SEO Stalkers are gonna have a harder time

I have also seen the same people leave comments on other blogs where I have commented in the past. Although I have never really used commenting as a means to gain backlinks (I just love to talk online, much to the annoyance of some people!) and seem to have built up a fair few links over the years as a result. Whether or not these are useful is anybody’s guess, most are nofollow and I have always assumed that they are not very useful, apart from on very busy blogs. But some people do insist on leaving comments after all of mine. I call this SEO stalking.
In fact, any form of copycat backlink building is a form of SEO stalking. Rather than be proactive and develop new ideas for yourself on how to promote your business, or engage with the wider community, you just look at the competitors that you admire and wish to emulate and do what they do. Maybe SEO stalking is not the right term, maybe lazy SEO is better?
Anyway, with Yahoo! Site Stalker dead what are we to do now? The answer at the moment (ignoring the multitude of premium services such as SEOMoz, Raven Tools, Majestic SEO and Search Metrics) seems to be Blekko.
Blekko is a search engine, but it also provides SEO data to users. I really get the impression that they are hoping to build greater visibility by appealing to the SEO crowd, as in doing so, more articles like the one you are reading will be written and the word will spread. Anyhow, for now, Blekko provide some excellent data on links.

What Blekko Offers SEOs

If you type a domain into Blekko you get to drill down into various sections to view more data, such as Cache, SEO, Links, Similar, Info, Source and Spam. There are also links to add a site to Blekko bookmarks which is a feature the other search engines are for some reason lacking!
For now, it is the SEO and Links that we are interested in. SEO shows a range of data on how Blekko sees your site. First up is total number of links for the domain, then a geographic breakdown of links by US state and then country. There is data on duplicate content, you can quickly view the robots.txt file and check whois information.
The Inbound Links data on Blekko, found in the right hand side navigation, provides not only the number of links it has found but also the anchor text, server location and data those links were found. If you wish to see how a competitor has recently steamed ahead in the search engines looking at the latest links may hold the answer.
Overall, Blekko looks like it has a lot to offer. For a free tool is probably does enough for most needs. SEO is of course much more than just getting links, and following the competition really is not always the best use of your time, but if you must do that, then Blekko can certainly help.
About the author: Jon Wade has been running a range of websites since 2006 and has written about SEO and web marketing over at Webologist.co.uk. He now focusses on building his local community site, EssexPortal.co.uk, which provides Essex business news and most recently a new page on Essex hotel reviews,  plus a wide range of other services.