On the plus side, they could incentivize posters to try harder to make quality posts. It could be a good system in some respects.
It already started to have that effect I noticed after theymos's implementation of the Merit 'system'. In some cases it's very obvious that people are posting in a very forced manner to obtain a Merit or two, but at least they put time and effort into their posts, and that's something we can all be happy with, and especially so when we're a few months away from now. I am glad that theymos allocated his precious time to getting this Merit system up and running -- people for so long were complaining about theymos to not do anything about spammers, and now it shows that he does actually do something to prevent further spamming.