Why is this notable? Am I missing something?
Of course, folks there complained about it being a non-issue, too.
I only know about any issues from reading HN, because absolutely no one I know has had any problems.
It's unfortunate some people have problems, but even if it may seem so, they don't speak for all 10.9 users.
Hope your problems gets fixed soon.
Also, about how many messages did you have in the inbox that worked?