The fix the did was a half-fix that never went through MS (and probably never through steam.)
That still a game breaking bug that pretty much destroyed multiplayer in the game for nearly a full 3 weeks.
The bug was pretty darn obvious, but they just released with it in there anyway. That's just releasing a half finished game in my book. Call me crazy, but my standards say that when you put the game on sale it should be free of game breaking bugs.