The idea has been floated around before and examples used from other companies where it had some success.
But I think there are several issues here that make it diffult to go with here at DDO.
If you put the expectation that a bug reported is worth "something", some players are going to only get upset when they feel their efforts did not reward them with anything (especially if it's something that has already been reported and known, as there is an official ticket/bug reporting system after all).
Then of course, we'd need someone to actually check and manage the sub-forum or thread and that'll just get worse and worse as it expands over time. Is this bug post a new one or a repeat of an old one? Has the bug actually come back or someone just threw something into the thread? Is it already in the actual bug tickets sent in via the official route?
Whilst we may think it costs the Devs nothing, even just going to check if a report is actually accurate and a bug exists takes up a Devs time.
And of course, how well detailed and accurate should such a "bug report" post be? Because we've seen "DDO is broken, Fix is" many times before. And technically, those posts would be correct and cover every bug out there. But it lacks anything of worth to actually action on.
In relation to that, we also have bug reports from players who had flawed testing of their bugs and just reported something in that they thought was a bug but was actually not what the actual bug is. Should these get a share of the pot that is rewarded in the end? Who gets what amount? After all, the first poster might have been correct indirectly and might have even lead to the actual bug being found and reported. So how much of the reward should they be given?
If the Devs appear to reward consistently to particular players often and players see that as favourtism, what should the Devs do then? No longer reward the player that got all the details in for them? Should that player then forgo putting in bug reports then as it's a waste of time for them and their efforts are not being valued enough?
It gets horridly murky quickly, where any resentment from players to devs, also expands out towards other players as well. There's a reason why such systems are not openly visible to everyone so as to prevent much of these issues arising, but some players don't trust that things are happening "fairly" without clarity either, and so the open thread/sub-forum approach is unlikely to happen given this.
If it does happen, it'll likely be an extension to the existing Bug Report system and players will just need to trust that everything is all hunky dory.
J1NG