I do not view it as appropriate for trust ratings to relate primarily to non-trust matters. By giving someone negative trust, you're basically attaching a note to all of their posts telling people "warning: do not trade with this person!". If we can get DT working well enough, in the future I'd like to prevent guests from even viewing topics by negative-trust users in trust-enabled sections, so you have to ask yourself whether your negative trust would warrant this sort of significant effect.

In particular, in my view:
 - Giving negative trust for being an annoying poster is inappropriate, since this has nothing to do with their trustworthiness. If they're disrupting discussion or never adding anything, then that's something for moderators to deal with, and you should report their posts and/or complain in Meta about it.
 - Giving negative trust for merit trading and deceptive alt-account use may be appropriate, but you should use a light touch so that people don't feel paranoid.
 - You should be willing to forgive past mistakes if the person seems unlikely to do it again.
 - It is absolutely not appropriate to give someone negative trust because you disagree with them. I'm disappointed in the reaction to this post. Although H8bussesNbicycles is perhaps not particularly trustworthy for other reasons, the reasons many people gave for neg-trusting him are inappropriate. You can argue that what he's advocating is bad on a utilitarian level, but he would disagree, and his advocacy of a certain Trust philosophy doesn't by itself mean that he's an untrustworthy person. DT selection is meant to be affected by user lists, and it is totally legitimate to try to honestly convince other (real) people to use a list more in-line with your views.
 
I'm not going to blacklist people from DT selection due to not following my views, since a big point of this new system is to get me less involved, but if a culture somewhat compatible with my views does not eventually develop, then I will consider this more freeform DT selection to be a failure, and I'll probably get rid of it in favor of enforcing custom trust lists.

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Now for this month's DT construction:

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