Updates to Team Fortress 2 have been released. The updates will be applied automatically when your Steam client is restarted. The specific changes include: 

Added 3 Heavy unlockables 
  • Natascha, The Sandvich, The Killing Gloves of Boxing 
  • Added 35 new Heavy achievements 

Added Arena game mode 
  • 5 arenas: Lumberyard, Ravine, Well, Granary, Badlands 

Added 2 new maps 
  • Badwater Basin, a new payload map
  • cp_steel, a community map by Jamie "Fishbus" Manson 

Changes 
  • Added server map timeleft to upper right of scoreboard
  • Added new firing sounds to The Backburner
  • Removed the Custom Tab in the serverbrowser, and added the Tags field to the base Internet Tab 
  • Increased The Kritzkrieg's uber-charge rate bonus from 10% to 25% 
  • 32 player servers can now support an extra slot of SourceTV 
  • Made the freezecam item panel description easier to read 
  • Players now broadcast whether they chose a team directly or use autoteam 
  • Added proper handling of cart blocking recognition to Payload maps 

Bug fixes 
  • Fixed bug where switching from flaregun-wielding Pyro to another class meant you didn't get a full ammo loadout on first spawn 
  • Fixed Spy watch arm not using team skins 
  • Fixed weapon switching preventing you from using secondary attacks for a 0.2s window after the primary became available 
  • Fixed players getting stuck in a bad animation state when class switching while spinning the minigun 
  • Fixed a loophole that allowed players to pickup weapons of other classes 
  • Fixed a bug that resulted in players earning more crit chance bonus in large, single damage events than they are supposed to 
  • Fixed an issue with the floating HUD +X health indicators that resulted in them appearing incorrectly 
  • Fixed a bug which caused the minigun spinning & firing sounds to occasionally stop while the Heavy was still firing 
  • Fixes the Loadout player model panel causing the in-game player facial animation to perform incorrectly 
  • Fixed spectators not having the target ID labels display correctly 
  • Fixed the cart alarm sound occasionally getting stuck on in Payload maps