Half the file size of the old TweenMax!
Timeline defaults that get inherited by child tweens
Advanced staggers everywhere
MotionPathPlugin (replaces BezierPlugin)
New random(...) capabilities
Get property values, with unit conversion capabilities
New "effects" extensibility
Relative ">" and "<" position prefix
Animate to a width/height o
All the nitty-gritty about GSAP 3, including what's new, what has been removed, and what has changed.