The forum should move the existing funds that are held by single users into multi-sig ASAP. I know folks like OgNasty are reliable, but shit happens and people die every day.
This is a fantastic idea, bitcoin has the multi-sig function, so why not use it ?
The funds were likely sent out before Multi-Sig was so widely used. I think all of the treasures are legit and all, but they are definitely not immortal!