I would like this yeah, it would be like sending them a PM but less private
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I would also hope that it notified you if you receive a new comment, as the only time I see my own profile is to update my signature / avatar. Even a simple E-mail would suffice.
EDIT:I don't think there's any danger at all of this possibly making the Member Dens redundant. With a den you can (from what I see) add seperate threads for example: "Ask me questions" "General chat" etc. Which I think would still warrant them if this "comment" thing comes to fruititon. And even if not, they're still nice to have
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