Yep, I think more sources are needed. Again, this is another Theymos problem that likely doesn't depend on what the community thinks about it, kind of like the perceived need for more moderators.
If the above statement is correct then I think it needs to be readdress. As big as Facebook is, majority of it's discission making is based on the respond gotten from it's users why? Because it's a community just as bitcointalk is. Therefore if the community members decides new merit source is needed he should look into the case and give a solution.
I still have trouble finding posters to merit.
You know why?, merit source don't get rewarded for this act that's why they're finding it difficult to see post worth meriting and most time when they do, they only give 1merit which is very discouraging.