Well, for one, the rates aren't the best... 0.04 btc after a month for 200 posts, or 0.0002 btc per post; Ritz, PD and the new UpDown.BT pay far more than this.
I don't have an idea about this forum, PD, Ritz and UpDown pay us for signature, but in this forum we get paid by posting. and they didn't have any specific rule for this (newbies, Jr Member etc) all you have to do just sign up, and make a new thread on Friday Payment and post your wallet addy.
But don't you have to make 50 posts a week anyway? My point is, for what they are paying, you make up to 3 times more as a Member here.
I can't give you the answer, even I just join in that forum... which is I'm trying to figure it out. For what? maybe just give them a traffic to they site.... dunno.