I blogged last month about the upcoming discontinuation of the Yahoo Site Explorer backlink counts in the Semify platform.

The short story is that Yahoo is discontinuing their API access on December 10, 2010. As a result, many people are not going to have this valuable source of backlink data. According to both Yahoo and Wn.com, you will still be able to get this data from the Yahoo Site Explorer web interface. It is merely the API that is being shut down.

Back in 2009, Yahoo started a new API service called Yahoo Search BOSS. Within the Yahoo Search BOSS api, there are a class of data calls called BOSS SIte Explorer, including the valuable inlink data (i.e., what they call backlinks.

As of December 2, 2010 Semify is migrating to the Yahoo Search BOSS inlink counts

During our QA, it was clear that these counts are very much lower than the old Yahoo Site Explorer counts. This will, of course, raise concerns for many customers who look quickly at the graphs and say "OMG, where are my links?" Be ready for this and arm yourself with this blog post and general awareness of the Yahoo / Microsoft search integration that has happened. Links are not being removed from the Internet, it is just that different sources of counting those links come up with different answers. What is of more interest to me is that:

The new Yahoo BOSS numbers match SEOMoz Linkscape

This is interesting and I'm still digging around to understand why. Are Yahoo and LinkScape using similar sources? Were the earlier numbers from Yahoo Site Explorer wildly exaggerated? Stay tuned and I'm sure we won't find out LOL... But seriously, let me know if you have any questions about this change. We are continuing to track backlink counts from SEOMoz, but as you know - those only update every 30 to 40 days. It is our hope that the Yahoo BOSS Search backlink numbers will prove as useful as the Yahoo Site Explorer numbers were. If not, we'll retire the graphs entirely. Until then, let's wish a sad goodbye to our old SIteExplorer friend.