Yahoo Answers is also STUPID. Full of not-all-that-bright high school and middle school kids trying to get help with their homework. I have written answers for some of those kids on Yahoo Answers, in subject areas where I know a lot. It drives me to despair. The best answers I see on YA are workmanlike.

On Quora most of the questions are reasonably good, most of the names are real, and some of the answers are brilliant.