The patch is now available and can be downloaded across all platforms. The update introduces many quest fixes as well as improvements in the gameplay mechanics. You can find the full list of changes below:

PERFORMANCE:
Overall improvements to performance, including some issues that may have been caused by 1.07.

UI:
[Japanese Only][PS4 Only] Fixes an issue where the background text of certain books would flicker.
Fixes an issue where part of the Kaer Morhen map would not display properly.

GAMEPLAY:
Fixes a rare issue where items would disappear from the stash.
Fixes a very rare issue which would cause Geralt to get stuck when trying to run.
The interaction pop-up will no longer appear on lootable objects that are empty.
Fixes an occasional glitch in one of the dwarf combat animations.
Heads chopped off during finishers will no longer disappear.
"Players can perform a roll just before landing to significantly reduce the damage caused by falling.
We've added a tutorial pop-up window explaining this to make it clearer."
In patch 1.07, the level requirements for certain items were scaled up, leaving some players stuck with only unusable gear. With patch 1.08, we are introducing the Wolven Hour potion. This potion will be available in everyone's inventory once they install the patch. It will reduce level requirements on all gear for a period of one hour. This will give players time to level up or find alternative equipment using the gear that was available to them in patch 1.05 but became unusable after patch 1.07. After one hour, the potion's effects will cease and the requirements for all gear will revert to their original, pre-potion values.
Fixes an issue where players were unable to compare their items with ones sold by merchants.

ACHIEVEMENTS:
Players will now be able to complete the Card Collector achievement.
Achievements are now working properly again and will be unlocked if players meet their requirements after installing this patch (PC version).

GRAPHICS:
Fixes an issue where interiors would sometimes not display properly on the minimap.
Fixes an issue where certain world elements would sometimes be missing and noticeable visual glitches would be present while in Novigrad.

QUEST:
Fixes an issue where players were unable to finish the "It Takes Three to Tango" quest, even though they had obtained wine at the Kingfisher.
Fixes an issue where Geralt would sometimes die after traveling to Velen in the quest "Something Ends, Something Begins."
The entrance to the area where the Sunstone is obtained will no longer be blocked off if the player exits it prematurely during "The Sunstone" quest.
Fixes an issue where players were unable to complete the "Get Junior" quest on certain occasions.
Fixes an issue where players were unable to finish the "Scavenger Hunt: Viper School Gear" quest due to a closed gate.
Fixes an issue where some players were unable to investigate rooms during the "Family Matters" quest, effectively blocking their progression.
Fixes an issue where players were unable to finish the "Hey, You Wanna Look at my Stuff?" quest.
Fixes an issue where players were unable to talk to Roche during the "An Eye for an Eye" quest.
Fixes an issue where Roche would stay at his camp instead of going to the Oxenfurt Bridge in the "Get Junior" quest.
Fixes an issue where, under certain circumstances, Yennefer would not appear in Oxenfurt during the "The Great Escape" quest.
Drowners will have a harder time killing Nidas during the "Black Pearl" quest.
Fixes an issue which led to an infinite loading screen during the "To Bait a Forktail..." quest under certain circumstances.
Fixes a rare issue where the basement was locked during the "King's Gambit" quest.
Fixes an issue where players were unable to free the merchant during the Person in Distress event in the Claywich area.
The trolls at the Circle of Elements will no longer attack Geralt if he opts for a peaceful resolution.
Fixes an issue where players were unable to talk to Roche during the "Brothers in Arms" quest.
Fixes an issue where Zoltan's card was unobtainable.

GENERAL:
Preparatory features paving the way for the introduction of New Game + in the future