Add some highlights to changelog (#18357)

Co-authored-by: Marc Mueller <[email protected]>

CHANGELOG.md

@@ -2,7 +2,25 @@
 
 ## Next release
 
-...
+### `--strict-bytes`
+
+By default, mypy treats an annotation of ``bytes`` as permitting ``bytearray`` and ``memoryview``.
+[PEP 688](https://peps.python.org/pep-0688) specified the removal of this special case.
+Use this flag to disable this behavior. `--strict-bytes` will be enabled by default in **mypy 2.0**.
+
+Contributed by Ali Hamdan (PR [18137](https://github.com/python/mypy/pull/18263/)) and
+Shantanu Jain (PR [13952](https://github.com/python/mypy/pull/13952)).
+
+### Improvements to partial type handling in loops
+
+This change results in mypy better modelling control flow within loops and hence detecting several
+issues it previously did not detect. In some cases, this change may require use of an additional
+explicit annotation of a variable.
+
+Contributed by Christoph Tyralla (PR [18180](https://github.com/python/mypy/pull/18180)).
+
+(Speaking of partial types, another reminder that mypy plans on enabling `--local-partial-types`
+by default in **mypy 2.0**).
 
 ## Mypy 1.14