I guess the approval of the posted comments and articles are subjective to a worker productiveness of the moderator for the benefit of the site itself. The idea of depending on the guidelines and as well as the terms and conditions of the site posted is the the rule to be followed by everyone. I guess the duration is circling to a week or two depending on the site exact process.

When you submit a thread, you receive a confirmation email that indicates the submission will be reviewed within 2 weeks (often they are reviewed much sooner). If they are not reviewed within two weeks, they will be automatically approved.