Katarina's patchnotes
How the patchnotes literally look, ofc people will attack me now on it , but seriously... this is literally what it is...
Base stats:
Just reseted the last 6 nerfs.
Her Q Gutted damage, HARD... Lowered poke potential, CD is toxic high...
her W
Gutted damage, Gutted CD, Gutted MS spam
Gains: DECAYING movement speed for the same duration as the old one, so basically after the 0.1 limit you got LOWER MS than the old spamable W... And CD is huge as hell
For now you lose tons of damage and mobility and lose a spammable slow that allowed you to counter mobile enemies and Vi/Jax/Udyr/Yis/Yasuo, with 
Her E
Gutted damage, increased CD (prove me wrong)
for compensation, you can spam it on some daggers that deal some damage that isn't really that compensating the already gutted damage... Removed ward jump... Basically your job is just to spam shunpo around and hardly do any actual damage compared to before... If your enemy is a bit smarter... You're instant dead.
Her R
Bad player buff : Cant cancel it by missclicking on enemy and basic attacking at first and last moment of the ult
If you get instant stuned, you do LESS damage at first moment cast... Because your "increased" damage, which is actually lower AD/AP scale, but people didn't notice that... cough as I was saying, you cast 5 daggers instead of 3 in 1 second, but if you get instant stuned, your first dagger does nearly half the damage from the old dagger., plus you don't have the Q damage 2nd hit dmg boost... so the ult is major gutted, unlike what ppl kept saying "buff buff".
Her passive: the same with some SITUATION, damage which is the compensation for the mobility and damage gut...
Basically, if think about it... You'll notice that this is a huge reworked, that pretty much gutted the JUNGLER and TANK potential you had before. I mean true most of you know that she can be played only mid, so you got your weird opinions that this kit is better... But actual ppl who know her old potential know that this is a huge gut to the tank build and to the jungler build...
Here's my 2 cents as a Katarina main since her release...
Glad nobody will care or I'll get hated/flamed/downvoted for it. Cheers