Ranked matchmaking arrived in Team Fortress 2 [official site] overnight with the Meet Your Match Update, letting you and your pals leap in and scrap to prove you're the roughtest, toughest, point-caputringest mercs this side of Dustbowl. Or find out quite how bad you are. How confident do you feel? Valve have also launched a little contest to decide which character class will next receive an overhaul: the Pyro or Heavy?
Ranked matchmaking arranges 6v6 matches with solo mercs and parties of similar skill levels. You get a fair fight, then, with random critical hits disabled and shotgun spreads fixed too. If you lose, it's all your fault. There are eighteen ranks to climb (and fall), and everything is of course tracked with stats and medals and things. To dissuade cheaters and smurfs from making new accounts, players do need to have a 'Premium' account (obtained either by having bought it, or buying something from the in-game store) and an active phone number. They really don't want Marlon Rando and his cheater pals causing trouble. Check the FAQ for more information on how it all works.
Valve have also added matchmaking to TF2's quickplay, which is a bit of a sticky issue. Before, the quickplay option would dunk players onto a random active server which met a few conditions like running certain maps and having Valve Anti-Cheat enabled. Now, it tries to arrange 12v12 unranked matches with similarly-skilled players. That might sound nice in theory, but players do need to wait for the match to be made. Players are punished if they leave matches too, receiving lower priority in matchmaking. That's a bit of a bummer. You can still hunt for a server through the browser but that is a lot more faff than pressing a button.
As for the Pyro and Heavy, Valve explain that this is WAR. To decide which next receives a class pack with new weapons, new achievements, and balance tweaks, they're having players fight for a side. Next time you launch TF2, it should ask you to pick - and all points you own will go to your fav. Both will be updated eventually but which do you want first?
The full changelog for the update is over here.