* Removed the "here's why some specific messages might be flagged as spam" in favor of a general explanation
* Bullet points, as a sort of checklist for people to go through (most likely to least likely)
* added, "whitelist email@example.com specifically", in case people can't whitelist a domain.
* took out the "make sure you enabled commenting!!" bit, that seems extraneous. you won't get comment notifications for comments that DON'T EXIST. :P
* took out the "check parental controls", as I don't think I've seen a recent case where that was actually the case.
* took out the "it's not our fault, except when it is" paragraph.
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