My understanding is that it was once meant to be almost tvtropes-like with a sort of back-and forth linking between pages about concepts on the wiki and posts which refer to those concepts on the main site (in the same way that tvtropes gains a lot of its addictiveness from the back-and-forth between pages for tropes and pages for shows/books/etc).

In programming, there's this thing called language reference (manuals or sites or whatever). You use them to look up the details of a concept that isn't clear in memory, or that you haven't seen before, and you also use it to point other people at the specific technical details of a functionality. I say this because that's essentially the usage I make of the LW wiki at present. They condense topic-specific or concept-specific information and then give branching paths to primary sources of information with more details and explanations, most of the time. ETA: Also, when possible and the article is of decent quality, I prefer to link to the Wiki rather than the blog posts linked in that wiki article. The summary is usually sufficient to jog the memory of people familiar with the LW concepts, people not familiar with the concept but interested will click the links and read the blog posts on their own anyway, and people not familiar but not interested will read only the summary, but wouldn't have read the blog posts if linked directly to them.