Using git for code review

At my workplace, I’ve recently been using git for code review purposes. I work on code in my own git clone, and ask a peer to review it. It works somewhat like this:

1. master branch is same code as currently in upstream.
2. Working to resolve issue #1234 pertaining to “Performance for gizmo”, I work on a branch 1234-gizmo-performance.
3. I mail a peer, John, with this information, as well as my repository location.
4. John adds my repository as a remote, lutzky. Then he branches review1 (or review2 if that is taken, and so on) at lutzky/1234-gizmo-performance.
5. John adds comments with nice big FIXME tags, which are highlighted in any decent editor. He commits this, the commit-message stating that it was code review.
6. John tags his final review commit (or, if he had no comments - lutzky/1234-gizmo-performance) with a reviewed1 (or reviewed2, etc.) annotated tag. Since the annotated tag includes all the necessary information (who tagged, when, and what), the number doesn’t really matter.
7. I merge john/review1, incorporate the changes (or reject them) and remove the comments. If no further review is necessary, I submit this - and once submitted, I merge this back into master.

It’s a nice system. I wonder what other methods there are of doing this.