My preferences for top level posts, which seem to be a higher standard than the community average, is that they should present some novel insight into a relevant topic, and reflect some research into previous work on the topic; or that they offer a deep review of a relevant work external to Less Wrong.
Bear in mind that those with lower standards will make more top-level posts.
Currently, the comment for which I've received the most positive karma by a factor of four is a joke about institutionalized ass-rape. A secondhand joke, effectively a quote with no source cited. Furthermore, the comment had, at best, tangential relevance to the subject of discussion. If anyone were to provide a detailed explanation of why they voted as they did, I predict that I would be appreciative.
Based on this evidence, which priors need to be adjusted? Discuss.