+++
There is a new command M-x replace-rectangle.
+** `C-x r t' (string-rectangle) no longer deletes the existing
+rectangle contents before inserting the specified string on each line.
+The `replace-rectangle' command can be used if deletion is required.
+
** The new command M-x query-replace-regexp-eval acts like
query-replace-regexp, but takes a Lisp expression which is evaluated
after each match to get the replacement text.