All,
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 behavior.