With this birthday celebration, Team Fortress is now presumably the same age as those people who call me swears when I hug them with my knife. Rather than us give Valve presents, the team has goodies in store: a hilariously annoying/awesome noisemaker, a party hat, and health and ammo kits have been turned into cake and gifts.
Best of all, there's an inflatable beach ball in spawn that you can shoot/punch/stab. You'll also find that gibbed players now sprinkle balloons and confetti across the landscape. You really should log into Team Fortress 2 just to see some of this stuff happen first hand.