antonaf - 12:10 am on Feb 26, 2006 (gmt 0)

Are you cross-linking your sites? Basically, do you have a link on your sites from another one of your sites (which share the same IP address). I know Yahoo penalize for this, not sure about Google, but it could be possible.

Also, I know a PR update is taking place, because one of my sites went from PR0 to PR4 in the last two days. Not sure how the PR update affects the SERPs (instantly)...just a thought!