Hmm. Nobody wants to talk to me
I guess you're all off at the beach.
Anyway, I did a bit of googling, I found these two articles that may be useful to anyone curious about pingbacks.
http://www.stonetemple.com/articles/...-and-seo.shtml
http://www.radicalbright.com/wp1/?p=5
I still don't know whether allowing pingbacks from other blogs does me damage because I have more outbound links.