diff --git a/relnotes/next b/relnotes/next
--- a/relnotes/next
+++ b/relnotes/next
@@ -5,6 +5,10 @@
  * The `rev-branch-cache` is now updated incrementally whenever changesets
    are added.
 
+ * `hg diff` now takes an experimental `--merge` flag which causes `hg
+    diff --change` to show the changes relative to an automerge for
+    merge changesets. This makes it easier to detect and review manual
+    changes performed in merge changesets.
 
 == New Experimental Features ==