Barry sums it up here, http://www.seroundtable.com/archives/015425.html it doesn't matter [to Google] if you use a virtual host or a dedicated IP, it will still count*
The interesting bit for me is in the referenced Slashdot article: "We do see a small percentage of ISPs every month that misconfigure their virtual hosting, which might account for this persistent misperception" Does anyone know what kind of misconfiguration can make a difference to search engine results?
I don't know the answer to that. I did however, find this article by Lisa on Bruce Clay's website: http://www.bruceclay.com/blog/archives/2007/03/which_is_better.html I also did this short write-up on the matter, doing a small comparison between the views: http://www.ginside.com/2007/1253/myth-buster-virtual-host-vs-dedicated-ips/
I think common sense also dictates this. As was pointed out in the original article most of the entire Web is on share IP accounts. It would destroy the rankings to make this a factor. Thanks for the post!