Here is the full post from Gypsylord:
At some point in the future a patch will come out. Contained within it will be a multitude of bug fixes for Vi. Wanted to give you guys some clarity on what exactly some of the fixes are and how they're going to affect you as a Vi player.
-Vault Breaker (Q):
-Vault Breaker will now always refund its CD and mana when interrupted
Currently Vault Breaker is sometimes being put on cooldown when Vi gets CC'd during its charge time. This is not the intended functionality. As a melee champ who focuses on autoattacks, losing the VB charge is already punishing enough for Vi. She should not be losing her move-block on top of that.
-Vault Breaker will now always stun for the intended amount of time (.5 seconds)
Currently VB, when hit at max range, is not stunning champs for as long as intended. Going to fix that.
-Vi will now always attack enemy champions after hitting them with Q
Currently Vi sometimes won't attack her enemy after landing a VB. Now she always will. Should be a good feel change. Q + Auto + E should flow right into each other much better now.
-Excessive Force (E)
-The responsiveness of Vi's attacks after using Excessive Force is being increased
EF currently hits twice as fast as a normal attack. This creates a longer space between an EF empowered strike and the attack following it. The end result? Excessive Force feels rather clunky and sluggish.
I'm decreasing the wind-down time Vi will experience after hitting someone with EF. This means the attack after EF will now come out slightly faster. Should feel a lot better and also add a good amount of power (faster attacks = more damage and dueling potential).
-Assault and Battery (R):
-Assault and Battery will no longer be canceled by stealth and the damage won't be negated by characters with CC immunity.
Currently A&B is getting dodged by things that shouldn't be able to dodge it. Not intended. The ONLY ways a champ should be able to avoid A&B is by going untargetable or putting up a spellshield. Olaf and Morg will no longer stop its damage and Akali will no longer be able to twilight shroud herself out of danger.
-Champions affected by Assault and Battery will no longer be able to cast spells after being knocked into the air.
Currently targets of A&B are able to cast spells like flash, troll pool, and tumble for about .25 seconds after being knocked up. The CC wasn't being applied early enough in the animation. This change should put an end to ADC's flashing away AFTER you hit them.
Not going to beat around the bush here. While these changes, from a design standpoint, are all intended to make Vi more consistent and improve her feel/flow, many of them are buffs. Will be watching her and tweaking as needed."