[[ You may wonder, why another q&a system, when there are plenty of them, Quora, Stackoverflow and even a lot of different Wiki?
I have been using Quora for a while, now writing the key difference between two systems.
<td>constant buzz and fun</td>
<td>arbitrary small/big thing</td>
Imagine, you have some life experience, which you gained over dozens of years. There is no too much narrative, just concentrated list of key points and reference to works of other authors. (Indeed, most of things are written out by others, except you are inventor of genuine technique.) Other words, you have answers, which things to do, and which not to do, perhaps with some details, based on your experience. And these answers are strongly proven by your life, you are responsible for them, despite other people may have another opinion and be also correct.
Project Identity is the way to summarize your knowledge at your full control. You are writing them once and then just giving reference. Records can be arbitrary small and can be grouped together by their properties and search requests. So answering the question is just creating proper search request. By your own or other person. Indeed, many answers implies some/lot reading, and a lot of work.
Quora, on the other side, requires an extensive narrative for each answer. Yes, some questions need answer just to be written in a few paragraphs without referring to basic manuals, and this is enough. Also, when summarizing your life experience, you may omit some things you consider insignificant, but looking at Quora question, you may recognize them. So, Quora and similar systems are really good for such cases.
The problem is, people are asking a lot of very similar questions in different variations. Having your experience summarized, it will be good just to give a proper search request, implying people to further read/work, perhaps accompanying with some short instructions how to move on. Yes, it is possible to maintain some copy&paste template and put it into answers with slight correction. Yes, it is possible to merge questions. But people still ask. And you really can become tired of this. So there is a need for some automation, giving proper answers for a new questions. Project Identity is aimed at this, however there will be a long way to make this perfect.
As an outcome, Quora produces constant fun and buzz, having a lot of sligtly varying similar answers instead of systematizing them. This is good to talk or look for whats new, but uneffective for summarizing your knowledge. Project Identity instead is aimed to concentrated summarizing your knowledge (answers), instead of dispersing your knowledge over a lot of sloppy questions, which is hard to maintain. I.e. write once, answer many. Have a concentrated work, regularly update and refine your knowledge, instead of producing a lot of buzz. It is tough, it is less fun, but this is more effective for a long term.
Another key point is the user interaction. Imagine, thorugh a lot of efforts you have picked some people you can trust to. Looking at question answers you may wonder it will be good to see how the people you trust to are treating these answers. However it is a problem to see even one person opinion (upvote) on particular answer, not even speaking about seeing whole picture of the all the people you trust. All you see is the averaged rating of all users. Sometimes it may hit. Sometimes it means just the answerer is just a popular writer and have a lot of followers, but the answer may be regular blabla or even bullshit. Really you may do not want to see neither top bloggers, nor their followers. Some things certainly have to be separate, like cake and barbeque, and making them average is a straight way to make slops. Even more, you may want to see the whole picture of all answers of all people you trust to. Impossible. Even for one person it is not so convenient. So, the Project Identity is aimed to deal with this. It is user-centric, you are fully controlling your knowledge, its structure and people you trust to, without coercion to be averaged by community.
A few words about Stackoverflow. It is technically-oriented and have strong moderation. So there is a very good chance to get correct answer at the top. The drawback comes from its advantage - it is very strict, question format is strictly limited. Just good technical q&a system without even without allusion to make something at your own.
A few words about Wiki. It is also community-driven, even with a less chance to maintain something personal than in Quora. Of course you may create your own Wiki server, but when you will invite other users, the problem will come back. ]]