What this means is that if you plan to have a somewhat "grown up" community you'll have to find a way to raise the bar somehow.
Some people have tried making more mature gaming communities, such as the owner of Insomnia who enforces a very strict posting guideline[1] and requires a paid subscription in order to participate[2], but I feel that these types of communities are often too restrictive in the types of content they can provide, often limiting themselves to specific discussions on higher level game mechanics of specific genres, and, as a result, lack the diversity found in forums like NeoGAF.
[0]http://www.neogaf.com/forum/showthread.php?t=390708 [1]http://insomnia.ac/commentary/posting_guidelines/ [2]http://culture.vg/subscribe.html