Just a quick rundown from the Live Letter.

GL is a trait, it only increases GCD speed, there is no longer a damage increase coming with it. Potencies have been adjusted to reflect this. This also means there is zero chance of losing GL.

Form Shift gives status 'Formless Fist' which allows the use of any weapon skill.

Tornado Kick is now a damage oGCD and does not affect GL at all.

SSS now has a movement increase buff associated with it when used.

From the short clip of Yoshi using Monk, Perfect Balance has been given the Ninja Bunshin treatment, you get stacks of Perfect Balance which deplete with weapon skill usage.

I did not see Riddle of Earth on his bars at all and it seems Dragon Kick still grants Leaden Fist. Whether Leaden Fist has been adjusted I don't know.

Anatman and the 3 fist forms are still present, what they do I have no idea, however Yoshi was in Fists of Fire for the demonstration, so maybe it has gone back to Fire Damage, Wind Movement speed and Earth Damage mitigation.