I got here through HPMoR, too, but not at all because of these discussions; I got here through Eliezer's links in the Author's Notes. Indeed, I had no idea this was the primary venue for MoR discussions until the link on hpmor.com made it obvious. I don't think it was very obviously linked to from anywhere on FFN before; or at least, I never saw it.

If we had dedicated forums, I think a series of banner "ads" ("Learn everything Rationalist Harry knows by reading the Sequences at Less Wrong", etc.), in addition to the frequent links to MoR-related posts by commenters, might be just as good as (or maybe better than) these suboptimal discussion threads for awareness and traffic.