You used to be able to gain recognition with thorough answers to domain-specific questions. But if you take a look at a lot of the "trending" answers on Quora, they all seem to be written by the same 10 Quora power users (Mark Bodnick, Garrick Saito, Venkatesh Rao, etc..)
The problem not so much the existence of these power users but the fact that they seem to only upvote amongst themselves and contribute to each others boards, creating a very exclusive feeling.