From Battlestar Wiki, the free, open content Battlestar Galactica encyclopedia and episode guide
Battlestar Wiki works by building consensus. Consensus is an inherent part of the wiki process. The basic process works like this: someone makes an edit to a page, and then everyone who reads the page makes a decision to either leave the page as it is or change it. Over time, every edit that remains on a page, in a sense, has the unanimous approval of the community (or at least everyone who has looked the page). "Silence equals consent" is the ultimate measure of consensus — somebody makes an edit and nobody objects or changes it. Most of the time consensus is reached as a natural product of the editing process.
When there are disagreements, they are resolved through polite discussion and negotiation, in an attempt to develop a consensus. If we find that a particular consensus happens often, we write it down as a guideline, to save people the time having to discuss the same principles over and over. Normally consensus on conflicts are reached via discussion on talk pages.
Consensus works best when all editors make a good faith effort to work together to accurately and appropriately describe the many views on the subject.
It is difficult to specify exactly what constitutes a reasonable or rational position. Good editors acknowledge that positions opposed to their own may be reasonable. However, stubborn insistence on an eccentric position, with refusal to consider other viewpoints in good faith, is not justified under Wikipedia's consensus practice. (Note that in the rare case if the "eccentric" position turns out to have merit, the consensus can change.)
Even if an editor's contributions appear to be biased, keep in mind that their edits may have been made in good faith, out of a genuine desire to improve the article. Editors must, in almost all situations, assume good faith and must always remain civil.
Consensus vs. other policies
It is assumed that editors working toward consensus are pursuing a consensus that is consistent with the consensus on how to do things on a wider scale - especially the neutral point of view (NPOV). At times, a group of editors may be able to, through persistence, numbers, and organization, overwhelm well-meaning editors and generate what appears to be support for a version of the article that is actually inaccurate, libelous, or not neutral, e.g. giving undue weight to a specific point of view. This is not a consensus.
Consensus in practice
Consensus does not mean that everyone agrees with the outcome; instead, it means that everyone agrees to abide by the outcome. The following description of consensus, from the Wikipedia mailing list, argues a difference between consensus and unanimity:
In fact WP's standard way of operating is a rather good illustration of what it does mean: a mixture across the community of those who are largely agreed, some who disagree but 'agree to disagree' without disaffection, those who don't agree but give low priority to the given issue, those who disagree strongly but concede that there is a community view and respect it on that level, some vocal and unreconciled folk, some who operate 'outside the law'. You find out whether you have consensus, if not unanimity, when you try to build on it.
Note: In disputes, the term consensus is often used as if it means anything from genuine consensus to majority rule to my position; it is not uncommon to see both sides in an edit war claiming a consensus for its version of the article.
Consensus vs. supermajority
While the most important part of consensus-building is to thoroughly discuss and consider all issues, it is often difficult for all members in a discussion to come to a single conclusion. In activities such as Requests for Adminship, articles for deletion or requested moves, consensus-building can be unwieldy due to the fact that more people participate than can effectively cooperate. These processes may have been somewhat misdesigned, in that they have not scaled cleanly. As a result, it is sometimes hard to determine what the consensus is in such processes.
To compensate for this, people first simply check if the criterion of supermajority is achieved, and on that basis make a first order assumption on how close one is to rough consensus.