Dev4vip, we have vBSEO and vBSEO Conditional Signature applications installed, but I am not completely sure on their settings, and what parts are enabled/disabled. I will have to look into it and get back to you.

The last I remember is that Conditional Signature is not yet enabled, but the nofollow might well be active. I think since we do not really limit our members on amount of active links in signature and give signature space good exposure, its only fair to HD to be able not to lose track of its own search optimization ability.