We are experimenting with this feature on Stack Overflow at the moment.
For the next few weeks, it may be on or off depending on when you hit the site.
As it stands (starting from the next deploy) ... [subject to change].
- Anybody can submit an edit to any post.
- Anonymous can submit edits to any post older than 1 day
- Any 2 Users with more than 1k rep can approve or reject an edit (there has been ample discussion about the "blocking" quality of this, we are still fine tuning this rule.)
- The owner of the post has 1-click reject rights, 1-click approve rights for the owner are being discussed.
- We are also discussing if 1-click approve/reject rights should be given to users with more than N rep
- If the queue fills up (20 currently) the feature is automatically disabled
- The UI that lists all pending edits is only available to developers at the moment.
All of this is subject to change, but from my last few test runs the quality of the edits are pretty good, most of the edits get approved.