Via the Steam Community:

GRAPHICS

• Fixed certain particle effects, like tracers, to fall back to mixed resolution for better performance when using low graphics settings with MSAA disabled.
• Improved lighting artifacts in various interior places when compiling maps.

MISC

• Teammate colors will now be assigned on official servers as soon as all players press ACCEPT. This will ensure that colors are correct during Pick/Ban phase, and during Warmup.
• Improvements in Charms reactivity physics system to better align with weapon animations.

Rumor has it:

• Size is close to 325 MB (with Workshop Tools installed)