[quote=mbl]
RPers and GMs who join/start RPs only to immediately drop out has always been a major problem on RPG, some rep system to help as an early warning would be nice, even if it is abused in some cases. But a simple +1 system wouldn't help that much anyways. :P
[/quote]

I personally think displaying the user's post count under the avatar/profile page is a good indicator as any.