Wikipedia - the free encyclopedia on internet - has become one of the fastest growing website on internet.Unlike other blog sites, one has to build consensus for insertion of views into the articles.It has by now more than 3 lacs articles in its english version.Best part of it is that it is editable by anyone without having login, which means you can see the page as search result on any search engine and edit the contents you want to at will.However, editing contents which are not agreed upon by other users may be removed (revert) by other users. Infact this revert war keeps one interested in the topic and is one of the greatest attraction among wikipedians --- to win a debate--- which keeps them regularly coming on the portal.This is the way community has grown .
However consensus may be build by a group of users who may be in great numbers endorsing each others views, hence people who are not good at following changes regularly and refraining from moving by majority rule may not find it a good place.Even though the policy says wikipedia is not a democracy --- most of the times, mostly the deletion proposal of articles are the ocassions when numbers do count.
Another criticism about this site is that it is written by people who are not experts, but this criticism has been nicely dealt with by the community by adopting NO Original Research Policy -- which means you cannot air your own view , you must cite credible sources which can be verified.
Still people find loopholes within policies in articles where opinions do count like Biographies of living people --- you can always find some credible sources with malicious content, Controversial issues of our time -- where both sides of views are present .These are the areas where edit war becomes extremely hot and frequent abuses are exchanged.
Although wikipedia has good policy for dealing with such abuses , they are interpreted according to the situation and users assessment. You can find similar situation yielding different outcomes.
Nevertheless wikipedia community is growing every day and has been recognised as a very important knowledge exchange tool.