It happened a short while ago. Two reasons:
(1) I needed to give people incentive to go back and delete old ads that had images attached to them,
and
(2) I needed another perk for Contributors to give people incentive to ante up for that as well.
Contributors get 5 meg of attachment space.
Now I realize that this could get to be a problem if people go over the limit on photos they post within the discussion forums, because there is no way for them to delete those attachments. Not sure what to do about that one. But this might just turn out to be another one of my bad ideas.
If enough people hate it, then I will just can this idea. Depends on how many people really use the discussion forums enough to notice, I guess.