Hitwise intelligence on the growth of Q&A sites, and Yahoo's continuing domimance-- Question & Answer Site Visits Up 118%, Yahoo Answers Is Clear Leader:
The market share of US visits to Question and Answer websites for the week ended March 15 was 118% more than during the equivalent week in 2007 - and over the past two years US visits to the category have increased 889% (Feb. ‘08 vs. Feb. ‘06), Hitwise said.
I've fooled around at Yahoo Answers asking serious questions and have yet to be satisfied with an answer. Most of what you see there are trivial questions. The site feels much more like Twitter than Wikipedia. This is not to say that Twitter is trivial, as it certainly is not, and I'm not saying that Yahoo Answers is trivial either. It's just that it doesn't work so well for getting quality answers to serious questions. This is an example of the type of question you'll see there, "Things you should never say to a police man?"
The reason that people use Yahoo Answers is more for connecting with other people and entertainment than answers to serious questions. Others, like Google, have tried to enter this space and have failed miserably. Where Yahoo is dominant right now, there's still plenty of opportunity for someone to enter into the Q&A game and do it right. Who will it be?