Not sure about the pic restriction specifically, but I think a lot of forums could be better off with a couple of flaming hoops for sign up and tiering up of accounts. Well "better" is a judgement call... but for sure its a under appreciated tool to sculpt a user base. It can do a lot more than just weed out bots and spammers.
If they remove the pic rule here, would this forum turn in to 90% 1-thread wonder users seeking bike support? Probably not but there is a way to find out..
