What is your intention? If you hope to espouse truth then I doubt it helps. People have lots of opinions - many of them uninformed or guesswork. And such a site has the risk of additionally weighing the prominent voices too much.
But assuming there is a sensible purpose then I think care must be taken to balance against prominence. User pages are prone to become hubs and mouthpieces of prominent people. Same for popular topics.
I think wikipedias approach of mentioning popular backers for claims is a good balance. Maybe this could be realized as an add-on to existing sites like Wikipedia. "What did X say about Wikipediapage Y?"
I'm not hoping to espouse truth in general - I don't think this is a good way to give people correct opinions about, say, neoreaction. I'm hoping to espouse truth about what people actually think, and I'm hoping that this will help to quell bullshit rumours.
So if someone starts a rumour that Eliezer is neoreactionary, someone else could add a section "Eliezer on neoreaction" saying things like: this rumour might be triggered by Eliezer's associations with Mike Anissimov and LW; Eliezer has never publicly endorsed neoreaction; in fact he has publi...
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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