Blizzard said:I think I've answered it at least three times on the last two pages, in varying degrees of detail. One of those times was inside a spoiler highlight. I will now answer it yet again, and refer you to teamfortress.com for (probably useless) other details you might want to know. Also, for anyone who doesn't know, you can right click on your Team Fortress game and check the update news. That often lists useful new features.
ACHTUNG ACHTUNG ACHTUNG ACHTUNG ACHTUNG ANSWER FOLLOWS
Weapons and hats are currently random. If you want weapons, play the game, or sit in spectator on a server. I suspect based on my experience that you get items a little more often if you are on a team instead of in spectator, but spectator still works. There are many achievement_idle servers, though some will kick you if you try to join a team, so you can just stay in spectator overnight or something.
I tried creating my own server to idle in, but I never got any unlocks. I'm not sure if I did something wrong, but I suspect unlocks happen more often when there are more players in a server. Your mileage may vary.
If anyone feels I have not answered the question at this point, please tell me. Otherwise, I shall merrily ignore any future questions about this topic. =P
ACHTUNG ACHTUNG ACHTUNG ACHTUNG ACHTUNG ANSWER WAS ABOVE
ANSWER THE QUESTION!!!!!!!!
Since this post is at the top, I'll relay this info from a few posts back:
http://forums.steampowered.com/forums/showthread.php?t=877982
"To earn weapon drops you currently have to be signed into the Friends Network on Steam.
If you are not receiving weapon drops please ensure that you're signed in.
Steam > Friends > Sign In!"