"You get the idea – this is a long way off. Years. More than two. Like three or more. Definitely not soon." - Games Workshop, three years ago.

Games Workshop has clearly been following a cycle of three years since 2017. That is the modern expected length of an edition of AoS or 40k, and has been since 2014.

The years between editions are when Games Workshop releases their non-mainline games. They have been doing this in a predictable fashion since 2017. It goes Mainline Edition, Skirmish Version, Hardcore/Forgeworld Version.

Note: Not listed are Necromunda 2017 or Adeptus Titanicus 2018... or Aeronautica Imperialis. Maybe the system is less perfect than I am intent it be.

But anyway, here are some good examples of this system in action with Warhammer Sci-Fi:

2014 - 40k 7th Edition (Mainline)
2015 -
2016 -
2017 - 40k 8th Edition (Mainline)
2018 - Kill Team 2nd Edition (Skirmish)
2019 - Apocalypse (Hardcore)
2020 - 40k 9th Edition (Mainline)
2021 - Kill Team 3rd Edition (Skirmish)
2022 - Horus Heresy 2nd Edition (Hardcore/Prequel)
2023 - 40k 10th Edition (Mainline)

And less reliable overrall, but equally steady since 2018, Warhammer 'Fantasy':

2015 - Age of Sigmar 1st Edition (Mainline)
2016 - Blood Bowl (Hardcore?)
2017 - Age of Sigmar Skirmish Supplement (Skirmish)
2018 - Age of Sigmar 2nd Edition (Mainline)
2019 - Warcry 1st Edition (Skirmish)
2020 - Blood Bowl (Hardcore?)
2021 - Age of Sigmar 3rd Edition (Mainline)
2022 - Warcry 2nd Edition (Skirmish)
2023 - Old World? (Hardcore/Prequel)
(Unfortunately both Bloodbowl and Warcry are quite neglected on the Lexicanum)

As you can see, these past two years Age of Sigmar and Warcry have been releasing in the same pattern but just one step behind their Sci-Fi Counterparts, 40k and Kill Team. So if the 40k prequel released last year, then this year we should expect to see the Age of Sigmar Prequel (A parallel they alluded to in one of their very first announcement teasers for the Old World*)

Another reason to back up the sense that the Old World will release this year, is that this is the 40th anniversary of Warhammer Fantasy 1st Edition. Those of us old enough to have lived through a few Warhammer or White Dwarf anniversaries know games workshop loves to commemorate.

So, on the contrary why haven't we seen any leaks for the Old World? We've seen a good chunk for 10th Edition Warhammer 40k. I believe It's probably primarily due to lower popularity. Of the three games 40k, Fantasy and Lord of The Rings, Fantasy was a very far behind third.See 'The Painting Phase YouTube Channel, peachy mentioned it recently. Even Age of Sigmar, though Clearly healthier, is still minute in popularity compared to the juggernaut that 40k is. It could also just be chance, leaks happen sporadically.

Some other information about the Old World you may already know:

Square bases are a certainty
Orcs will be Orcs
You will be able to use your old models
It will be primarily focused on the 'Old World' part of the Warhammer Fantasy map (i.e. not the Americas)
It is a prequel to Fantasy, set in the time of the Three Emperors, approximately 300 years ahead.
The Old World and Total War: Warhammer III are somewhat coordinated in their designs. Examples including Kislev and Cathay.
It will be Forgeworld-managed. That is not to say it will be all Forgeworld resin, indeed Forgeworld itself seems to be disappearing more and more into normal GW plastics.

Some rumours and/or speculation I've heard about it that I believe makes sense:

Confirmedish (They will have PDF rules): There may be Chaos Dwarfs - The refresh of the Legion of Azgorh has been long rumoured at this point. I remember even before the models were removed from Forgeworld I knew they were not much longer for this world. There are going to be Chaos Dwarfs (maybe there already are?) in Total War: Warhammer III. If the teams are coordinating, then it seems there would logically be new Chaos Dwarf minis inbound.
Confirmed: Base sizes may be increasing: https://www.youtube.com/watch?v=hXCDlN2L3-0&t=270s (added 2023-03-08)

Complete list of Warhammer Community Articles about The Old World:

Citation Needed because my dumb brain can't work out where to find it.