I have been getting lot of emails from people to delete forum profiles. Not sure if you can see this link but still ( http://www.mbaguys.net/member.php?u=87810
) and this was a spam profile created for a link drop and I was contacted to remove that profile by another SEO expert that is being hired to clean things up and so possibly this is what people to get started getting compliance with Penguin.
I don't have any such emails for G4Ef possibly because site became nofollow pretty early and that was not the case with MBAGuys
Wanted to add that just to make life easier for people who are willing to remove their links now member profiles are only visible to members on MBAGuys