Via [url=https://steamcommunity.com/games/TF2/announcements/detail/3542669318977720919]the Steam Community[/url]:

[quote=Valve]- Fixed a server crash related to multiple heavies spam firing their weapons
- Fixed trigger_add_or_remove_tf_player_attributes not interacting well with the status of other attributes
- Fixed trigger_add_or_remove_tf_player_attributes not updating player speed correctly
- Fixed spectators not being able to be kicked in Mann vs. Machine on official Valve servers
- Added support for custom sounds, soundscripts, soundscapes, navmeshes and particles in workshop maps

- Added a SetModel input to all entities with a model
- Mappers: This replaces the previous 'addoutput modelindex' method that was used for overriding an entity's model

- Added SetPlaybackRate and SetCycle inputs to all entities with a model
- Added a spawnflag to point_hurt to bypass Übercharge
- Added OnDeath output to tf_zombie entity
- Updated 'maps *' console command to show workshop maps
- Updated the Create Server menu to show workshop maps

- Updated ctf_crasher
- Giants should more reliably be killed when they drop or capture a flag
- Fixed a minor clipping issue on the ammo pickup by the arches[/quote]

Rumor has it:

- Size is ~35 MB