There are periodically competitions in which prizes are given out for top rankings, but in general no.
WikiAnswers has thousands of contributors (volunteers) who are 13 years old. However, they are not being paid for their contributions, as they are volunteers on the site. WikiAnswers is not hiring 13 year olds to work on the site to be paid at this time.
While there are paid staff that may answer questions on occasion, they are being paid for specific areas of work related to the site and its maintenance. And you can win prizes with the contests!
The Nobel Prizes are not awarded for the field of psychology specifically because Alfred Nobel's will specified specific categories for the prizes, and psychology was not included. However, advancements in psychological research and contributions to societal well-being are recognized in other prestigious awards.
Changes are constantly being made. Every second, more than a few contributions come in. So to answer your question, the last time WikiAnswers was edited was less than a second ago. To get a better idea, see the related link below.
Ultimately, you run the risk of being blocked - either temporarily or permanently. Even Wikianswers has a 'code of conduct' that contributors (and supervisors) are expected to follow. The rules are there for a reason - to ensure the smooth-running of the site, and to ensure contributions are meaningful.
WikiAnswers is only as good as the people who answer the questions. Given that this is a global site, with people of all ages, genders and intelligence making contributions, the vast knowledge-base that has built up is constantly being updated.
Yes and no. Some people feel good about making contributions to WikiAnswers because they are trying to improve it. However, some people think of it as just fun. Personally, I do it for fun, but I do feel good about being able to answer people's questions.
There are many prizes. You get 1 prize from 25 missions complete then 50 then 75 then 100 and so on.
Depending on the popularity of the category, it may or may not be at all difficult to make enough contributions to be listed as a Top Contributor of a category. As such, being a Top Contributor in and of itself doesn't mean much. It's the quality of your contributions, not the quantity, that will help you "earn your mark."
Currently, you are not required to register to WikiAnswers in order to edit or answer questions, to view our database, or to ask a question, among other simple tasks. Unregistered users, however, will not have bio pages, a running total of their contributions, or a message board to send or receive messages with other users on WikiAnswers. They also are not able to receive WikiAnswers RSS feeds via email. Perhaps sometime in the future, though, WikiAnswers may require registration in order to access certain areas of the site, but this is far from being released as such, if ever.
Maybe it is because WikiAnswers likes being family safe.
To exist, is the act of being real, or of being. WikiAnswers is of course the website containing this very question, so yes, it does in fact exist.