Via the Steam store:
ValveMatchmaking Changes
Competitive Revamp
- The matchmaking system used for Competitive Mode has been overhauled. Players will now be ranked using a model based on the Glicko rating system used in CS:GO.
- The old 18 Competitive ranks have been consolidated into 13 new ranks. You can view the new ranks on the updated Competitive FAQ page (http://www.teamfortress.com/meetyourmatch/faq/)
- Competitive ranks have been reset and players must win 10 matches to earn a new Competitive rank
- Note: The previous system started everyone at Rank 1, and required - in most cases - considerable time for players to reach a rank that properly reflected their performance. The new system - by way of placement matches - considerably shortens the time required to reach an appropriate rank
- The requirements to access Competitive Mode have changed: If you do not own a Competitive Matchmaking Pass, you must now be at least Casual level 3 in addition to being a Premium user and having a valid phone number associated with your account.
Casual Improvements
- Casual Mode now uses the Glicko skill rating system behind the scenes to better create balanced matches and group players by skill level
- The maps listed in the Casual matchmaking screen are now sorted alphabetically
- Added ctf_sawmill, ctf_well, cp_5gorge, ctf_2fort_invasion, and ctf_foundry to Casual Mode
- Updated the match-end map voting to only vote on maps for the current game mode (if you are playing Payload, you will only vote on Payload maps)
Queue While Playing
- You can now queue for a match while already in a Casual or Boot Camp match
- While queued and in-game, queue status will be shown in the top right
Multi-Queue
- You can now queue for multiple match types at the same time
- Players can queue for all match types in parallel, but accepting a Competitive or Mann Up match will remove the player from other queues
- Players who are in a party and not the party leader are now able to freely browse any of the matchmaking menus
Gameplay Changes
Flamethrowers
- Flamethrowers were able to do full damage regardless of the spread of their flames, rewarding maximizing flame spread over focusing on a target. We've made changes geared toward preserving the current damage range of flamethrowers, but requiring better aim to do so.
- Flame damage per second now ramps up based on density of flame encountered, up to 200%
- Initial flame damage per second reduced by 50%, resulting in the max damage being unchanged
The Dragon's Fury
- We are happy with the design of this weapon, and the playstyle it brings, but it should require tighter hit tolerances in order to reach the higher-end of the damage range
- The size/radius of the fireball has been reduced by 25%
- Bonus damage against a burning target now requires the fireball's center to make contact with the target's hitbox
The Gas Passer
- We found a couple of issues with the Mann vs. Machine upgrade "Explode on Ignite" that resulted in it doing far more damage than intended. We've increased base damage to help offset some of the reduction in output these fixes bring about.
- Changes to the "Explode On Ignite" upgrade in Mann vs. Machine
- Damage from the upgrade no longer counts toward the refilling the item's charge meter
- Fixed an issue where explosive damage could be reapplied for each target in the gas cloud
- Fixed the triggering bot not taking explosion damage
- Increased explosion damage to 350 (from 250)
The Axtinguisher
- The slow deploy time -- which is there to help "pay" for the burst-damage this weapon is capable of -- hasn't been very well received, and we agree that it feels awkward. The design goal of this pass is to embrace the concept of a finishing-move weapon -- which requires planning, timing, and introduces opportunity for "combo" gameplay.
- New design:
- Attacks mini-crit and then extinguish burning targets
- Receives a damage bonus based on the remaining duration of after-burn
- Added: "Sketchek's Bequest: Killing blows on burning players grant a speed boost"
- Base damage reduced by 33%
- Holster speed 35% slower
- No random critical hits
The Thermal Thruster
- We erred on the side of conservative with the initial design -- as this item introduces a lot of mobility to a class that's typically lacked it -- but having watched players for a while, we think it is safe to make it easier for Pyros to switch back to their weapon
- Holster time reduced to 0.8 seconds (from 1.1)
The Sydney Sleeper
- Jarate is a powerful effect, and this weapon makes it too easy for one Sniper to substantially increase the damage potential of their team. And, unlike the Jarate jar, the infinite-range of the rifle means the Sniper can be far away from danger. These changes are designed to preserve the "Jarate Rifle" identity, but tone it down, add more reward for the Sniper's skill by allowing higher first-shot damage output, and offer a way for players who want to focus on providing area-of-effect Jarate to recharge their Jarate jar more quickly.
- Fully-charged body shots and headshots no longer splash Jarate on players around the target
- Reduced length of on-hit Jarate to 2 to 5 seconds (from 2 to 8 seconds)
- Added: "Nature's Call: Scoped headshots always mini-crit and reduce the remaining cooldown of Jarate by 1 second"
The Short Circuit
- The current design of zapping projectiles is interesting, but we're not happy with how much it can be done. While it would be easy to simply increase the metal cost (which we've done before), it would quickly push this weapon into the rarely, if ever, used category. Instead, we've changed the fundamental behavior of the weapon, such that it requires a bit more anticipation and positioning from the Engineer, has more skill depth, and increases the team support potential of this weapon.
- Alt-fire attack changed to launch a medium-range, projectile-destroying energy ball. Requires 65 metal.
Pretty Boy's Pocket Pistol
- We underestimated how much health high-skill players would be able to recover during combat.
- Reduced maximum (close-range) per-hit heal amount to 3 (from 7)
The Panic Attack
- The recent redesign left this weapon feeling a little weak close-in, so we've increased the damage potential at point-blank and close range.
- Reduced worst-case shot pattern spread by 40%
- Reduced damage penalty to -20% (from -30%)
The Atomizer
- This is basically a bug fix. Players could perform a double-jump and then quickly switch to this item and eek out a third jump. The goal of the previous change was to require players to commit to this item in order to gain the extra jump.
- The weapon must now be fully deployed before a triple jump can be performed
Part two: http://www.teamfortress.tv/post/851359/tf2-update-for-3-28-18
Part three (RHI is over here): http://www.teamfortress.tv/post/851368/tf2-update-for-3-28-18