I am sure this has already been discussed, but just in case, here goes my two cents:
The post in http://breasy.com/blog/2007/07/01/implicit-kicks-explicits-ass/ explains why implicit metadata (like Google's PageRank) are better than explicit metadata (Like Digg votes). Making a comparison to Wikimedia, I'd say that Prof. Luca's trust algorithm is a more reliable way to determine the quality of an article's text than the Flagged Revision Extension. However, the point of the latter is to provide a stable version to the user who chooses that, while the former displays to which degree the info can be trusted, but still showing the untrusted text.
What I'd like to suggest is the implementation of a filter based on the trust calculations of Prof. Luca's algorithm, which would use the editors' calculated reliability to automatically choose to display a certain revision of an article. It could be implemented in 3 ways:
1. Show the last revision of an article made by an editor with a trust score bigger than the value that the reader provided. The trusted editor is implicitly setting a minimum quality flag in the article by saving a revision without changing other parts of the text. This is the simpler approach, but it doent prevent untrusted text to show up, in case the trusted editor leaves untrusted parts of the text unchanged.
2. Filter the full history. Basically, the idea is to show the parts of the to the article written by users with a trust score bigger than the value that the reader provided. This would work like slashdot's comment filtering system, for example. Evidently, this is the most complicated approach, since it would require an automated conflict resolution system which might not be possible.
3. A mixed option could be to try to hide revisions by editors with a lower trust value than the threshold set. This could be done as far back in the article history as possible, while a content conflict isn't found.
Instead of trust values, this could also work by setting the threshold above unregistered users, or newbies (I think this is approximately equivalent to accounts younger than 4 days)
Anyway, these are just rough ideas, on which I'd like to hear your thoughts.