We've disappeared ...

Well, not literally of course. The statement refers to one of our client sites.

One of our clients has a site which sells a very sophisticated swimming pool coating which reports inbound links on Yahoo!, but the site itself doesn't appear to be indexed by Yahoo! That is, it was properly indexed by Yahoo! until mid November and then it disappeared from their index. The inbound links have continued to be reported and actually increased after the site disappeared from the index. Google first crawled the site a few days after Yahoo! and has continued to crawl it, deeper and deeper since it was first indexed.

Do I have an answer for this kind of inconsistency? No, I'm afraid not. We are going through the process now to try and make sure that this kind of oddity doesn't happen again.