Valve has issued one more update for Team Fortress 2 today, apparently another attempt to bring balance to the method that allows for unlockable weapons and items. Achievement based unlockable items are back.
But according to the newest update, those milestone achievements are an "additional way" for Team Fortress 2 players to get newly added unlockable items like the Cloak and Dagger or Huntsman. Seems the randomized drops ushered in with the Spy/Sniper update are still in.
Valve issued an update to the way that those randomized drops were handled earlier this week, but it looks like it's now giving players more options. All those pros and cons for each method may add up to an acceptable solution. We'll see!
Team Fortress 2 Update Released [Steam]