Don't include pages were the last edit was Fred's. RecentReplies is useful for allowing Fred to easily learn from PeerReview, without becoming a RecentChangesJunkie.
Intuitively the last option seems most likely to correspond to the concept of "recent replies". It allows for a long period of time between Fred's comment and the reply, without continually bothering him with edits to an active page that he's lost interest in.
A related view onto RecentChanges would be RecentRelatedChanges for Fred's signature.
The above text is PrimarilyPublicDomain
[CategoryWikiTechnology] [CategoryUnimplementedWikiTechnology] [CategoryRecentChanges]