BigDave - 8:18 pm on May 14, 2004 (gmt 0)

I would doubt there is a shared blacklist. But sometimes there is value in working with a competitor against a common enemy. And lots of people at google have the phone numbers of their counterparts at yahoo, and visa-versa.

In this case, it is not just a case of improving their own SERPs, but trying to get rid of a thorn in their posterior.

They found a legitimate reason to get rid of the listing, and since they could also see value in having that company get no traffic, they pointed out the problems to the other major player.

This way they get rid of them without having to go through another searchking type of "scandal".