Via [url=https://steamcommunity.com/games/TF2/announcements/detail/3711587913700645622]the Steam Community[/url]:

[quote=Valve]- Fixed floating 'Bonus' label in the middle of the screen while working on certain contracts
- Updated the Clown's Cover-Up to fix some clipping issues, fix the LODs, and update the equip_region
- Updated the Celestial Summit Unusual effect to reduce the particle count
- Updated the Potion Explosion Unusual taunt effect to remove the delay when starting the effect
- Updated glowing eye materials on Voodoo-Cursed Souls and Übercharged players with community fixes from Liam Stone (boba)

- Updated the Carry-Van
- Fixed the rigging on the straps to avoid clipping when running
- Fixed misplaced ambient occlusion on the material
- Fixed rim mask being black in places it wasn't supposed to
- Fixed a hole in-between the window and top of the van
- Fixed LODs to represent above changes

- Updated the Dead Man's Party Unusual taunt effect
- Added fades to hand sprites
- Improved effect composition on fast-moving taunts
- Fixed some particle sorting issues

- Updated cp_lavapit_final
- Fixed a skybox exploit in the underworld

- Updated pl_spineyard
- Fixed an exploit that allowed players to get outside of the map
- Fixed missing cubemaps

- Updated pl_corruption
- Replaced some of the materials and models
- Adjusted collisions near some wooden beams by point A
- Adjusted prop fades
- Fixed some minor texture issues
- Fixed teleport trigger in one of the spawn rooms being too late to activate
- Minor adjustments to improve your sanity

- Updated cp_degrootkeep_rats
- Fixed players getting stuck in the door when entering the Rabbit Hole at the same time as an enemy player
- Fixed a hidden perch in the balcony overlooking C

- Updated arena_perks
- Replaced the Cloaking perk with the Patience perk (gain up to 7 health/sec)
- Fixed missing barricades in the voting area
- Fixed certain items having missing textures on the map
- Removed crumpkins (with help from LizardOfOz)
- Fixed stalemates causing extra rounds where no perks would appear
- Added a new HUD, with an alive player counter

- Updated zi_murky, zi_atoll, zi_devastation_final1, zi_woods, and zi_sanitarium
- If a game is in progress and there are no players on BLU team or RED team the game will now end
- Fixed a bug that allowed Dead Ringer spies to die without triggering a round loss
- Fixed a bug that caused Zombies to not see combat text correctly
- Fixed a bug that caused Rocket Launchers and Sticky Bomb Launchers to start with a low ammo
- Fixed a bug that caused changing player loadout to kill human players (particularly on Murky)
- Fixed an issue with missing particle effects for Medic's Heal ability
- Adjusted the number of Zombies selected at round start for low player counts
- Corrected unintended changes in the last update
- Changed the damage dealt by Zombie Soldier's Stomp
- In the previous update, Soldier would instantly kill his stomp target. This was not intended.
- The new damage calculation is (10 + fall damage x 3). This is the same as the Mantreads.
- Changed the Sentry Gun to deal 40% damage to Zombies
- In the previous update, this was 35%. This was not intended.
- Added a sound effect to Pyro's explosion of flames on death
- Removed some debug print statements
- Reworked Demoman's Blast Charge to fix several exploits and bugs
- These changes should also make Blast Charge more reliable and less frustrating to use
- Blast Charge is now triggered based on the player's velocity
- When player's speed drops below a threshold while charging, they explode
- Additionally, anything that would usually interrupt a shield charge will now trigger the explosion
- Fixed a bug that caused ÜberCharge applied by Blast Charge to persist longer than intended
- Fixed a bug that caused Blast Charge to fail to kill the player in situations where the player should be killed
- Fixed a bug that caused Blast Charge to briefly display the player's first person view before detonation
- Fixed a bug that caused the player to be unable to attack, jump or duck after surviving Blast Charge
- Fixed many bugs that caused Blast Charge to fail to detonate
- Fixed many bugs related to Blast Charge being cast at the same time as being converted to Zombie

- Updated zi_atoll (additional changes)
- Fixed the missing texture on the turbine building's roof
- Added areaportals and occluders in and around buildings
- Added extra nodraw brushes under the level and buildings to improve vis calculations
- Added prop fades on bushes and rocks
- Adjusted push triggers on trees
- Minor clipping adjustments
- Changed func_brush on roofs to func_movelinear so that corpses don't fall through
- Added soul gargoyle spawns
- Added a santa hat that spawns on the anchor when smissmas holiday is enabled
- Fixed cubemap reflection issues
- Fixed the seam between the 3D skybox and the playable level
- Aar fed the spinning cat

- Updated zi_devastation_final1 (additional changes)
- Replaced sewer exit to the 2nd floor with a ladder
- Changed sewer exits to no longer require crouching/prop jumps
- Fixed missing respawn trigger in the sewers
- Adjusted spawn positions of Zombies and Survivors
- Fire now ignites players
- Adjusted lighting in sewers to be slightly brighter
- Reduced round timer to 3 minutes
- Lit up 2nd floor car corner[/quote]

Rumor has it:

- Size is close to 250 MB