UPDATE 4PM BST: The patch is 15GB on console and between six-15GB on PC, community manager Marcin Momot has revealed. The Hearts of Stone expansion will be a separate download (comes out 13th October). But according to Momot, speaking in an email, the HOS download will be "considerably smaller".
The @witchergame patch 1.10 is going to be around 15gb on consoles (depending on SKU) and between 6-15gb on PC (depending on platform).— Marcin Momot (@Marcin360) October 8, 2015
ORIGINAL STORY 1.45PM BST: Witcher 3 patch 1.10 has been detailed and the notes stretch on for pages - there are more than 600 changes! "The update itself is right around the corner and should be here in a matter of days," community manager Marcin Momot said on the game's forum - and that's on all platforms.
Among the many points is word an Xbox One memory management issue has been fixed, as have the mini-freezes on the console when looting. There is no specific mention anywhere of PlayStation 4, but there are many more quest-specific performance issues fixed besides.
There are a number of changes to the user interface, apparently, particularly to the menus for Alchemy and Crafting, and to inventory sorting for item types.
Reams of glitches are addressed, including many to do with starting and playing a New Game Plus. I was going to post the full list here but, well, it's massive, so it's best linked to.
"It's the largest collection of fixes, improvements and various enhancements we've brought to The Witcher 3: Wild Hunt to date," Momot wrote. "All told, it packs a pretty impressive 600 changes, including fixes for a load of quests, optimisations that'll make things smoother on PC and consoles, over 150 stability improvements to iron out hiccups, additional conversations with key characters that will enhance your relationships with them as well as the story as a whole, and a major and much-awaited fix that should take a good bit of the pain out of dealing with items in the inventory by improving how items are ordered and sorted."
The Witcher 3 welcomes a meaty downloadable story add-on next week in expansion Hearts of Stone, priced £8. It should last around 10 hours. I played a couple of those hours last month and thought it showed a relaxed, playful side of developer CD Projekt Red. It didn't quite constitute an 'expansion' for me, but for £8 it's generous and hard to argue with.