The corpse of Google Answers hasn't even gotten cold yet, having just shut down about a month ago, but Amazon is quietly launching an answering service of its own to compete with Yahoo's answering service.
From what I can see from the beta, it looks like Amazon's Askville service will follow the Yahoo user-driven model, rather than Google's for-pay expert-driven model, which apparently didn't work too well for them. With Yahoo Answers and Askville, users submit questions which are then answered by other users, and the whole thing is free.
Not sure why Amazon's getting into this space, but Askville does have some nifty features. For one, answerers can't see other submitted answers until they submit their own, so every answer will be completely independent, That gives Amazon a more reliable way of ranking and evaluating answerers no matter when they chime in, and also prevents cheating and copying. As answerers prove themselves to be trustworthy, they "level-up" and gain more privileges on the site.
Another facet of Askville is the online currency it's introducing called Quest Coins. These are awarded for performing certain tasks on the site like providing answers (or questions), or rating answers. Quest Coins can also be lost for abusing the service. Amazon says a future site called Questville.com, launching in 2007, will give users a way to use these Quest Coins to enter contests, or exchange them for prizes