cabbie - 9:25 am on Oct 1, 2004 (gmt 0)

>>>Not sure if this is related, but I have today seen a couple of my AFFILIATES websites replace the URL of my own website in Google.<<<
I don't like to start a controversy but if a site owner wants affiliates then he has got to expect a good affiliate to replace him in the serps.A smart SEO can easily make google rank their affiliate referrer code in place of the sponsors page.
If you want affiliates then let them do what they do best and you concentrate on what you do best and supply the goods bought.
And don't think that just because the aff ref code is scoring in the serps that you would've ranked in the same place for the same keyword.