i see there's plenty of interest in this subject (especially from the Emeritus members) ... i'm sure you don't need to be told of similar sites popping up all over the web, but there is one in particular that has invoked a posting restriction that seems not only logical, but fair ...
here is their posting guideline (related to number of posts only) ...
Currently, you may post one poem per day in a maximum of two forums ONLY.(there are several forums, not unlike Passions). This is an attempt to prevent forum flood. If you do not comply with this rule, your most recent posts, including any comments made on them, will be deleted. You may however, make as many reply posts as you wish. As a general principle, commenting on other people's work is a good way of "getting yourself known" in the forums, and most people will be willing to comment/critique your work in return.
as i stated above, you don't need me to tell you of the competition out there, but the above policy sure makes sense to me (particularly in light of some of the more troublesome server and technical difficulties that have caused the site to crash) ... thanks again for a great site and i hope i'm not making more out of this than there appears to be ...