I think most of you know more than I do about the dynamics of user contributions to the Wikipedia, but I am seriously worried that showing stable revisions, rather than the most up to date revisions, will change for the worse how the Wikipedia evolves.
For one thing, this would delegate spam fighting almost entirely to a cadre of editors: others, even though they are motivated contributors, would not bother manually checking the latest page for every page they read, and thus, they would not discover whether the latest page is altered. The "good samaritan" phenomenon of people casually landing on a page, and fixing it, would be much reduced.
I fear even the incentive to edit pages would be reduced. People are motivated by instant gratification. Anonymous users, while they contribute a lot of spam, contribute also the majority of the factual, correct, and informative content of the Wikipedia (this is just a matter of statistics; I could easily post statistical data on this). Already now, the experience of an anonymous user contributing to the Wikipedia is not very positive: often, well-intentioned contributors are reverted, rather than helped, because they violate some style or convention or other thing they are not aware of. I fear that if we introduce the extra step, that their contributions will be put in a sandbox, maybe with many alternative versions by different users, and no clear probability that their version will be at some point included, we will provide a major discouragement for all those contributors.
Not all on-line communities are successful. The Wikipedia so far has been wildly successful, and I am worried at the change of something as fundamental as the principle of wikis: always show the last revision, make it easier to undo spam than to do it, and trust that most people are helpful. I am worried that the inflow of contributions, and especially, the variety and background of contributors, will shrink significantly. I am worried that dedicated contributors will continue to contribute, but the casual users, experts of some domain, that so far have contributed a very large proportion of the factual content of the Wikipedia, will withdraw.
The proposed behavior of the flagged revision extension is to show the
last reviewed version only to anonymous users. I submit that this is
should be default behavior for ALL users (subject to personalization
settings override, I guess). The question here is not just of
vandalism control, but also of making Wikipedia's content creation
process more deliberative. The power to command an article's content
by submitting the last edit is an incentive not only for vandalism,
but also the sort of uncivil version contention that has long been
damaging the community's social fabric. In making the last reviewed
version of an article the default view for practically ALL users, we
remove the incentive for not just vandalism, but all sorts of unsocial
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