Karma is generally referred to as "good", so the higher one's Karma is, the more his chance of being reincarnated as an overall better being. Applying to the forums, status change could occur if the karma reaches a certain level, which can be analogous to reincarnation as a higher being. Also, the lower your karma, the lower your chances of being born a better being (in fact, one may end up as a pig or a snake, etc.); so, the lower your Karma, the lower your status in society (in this case, the forum community; but that status is solely based on the amount of Karma) and the fewer perks one gets to enjoy (which is true, since there's a Premium section of the site, which can be attained when one reaches Nirvana, which is the highest amount/level of Karma).