The news of the game's new payment model was announced in the below video by Fable Legends' game director David Eckelberry, via the Fable Legends website.
In the video Eckelberry talks about what this new direction will mean for the game - it sounds like he is basically stating it won't be a 'pay-to-win' title, as every unlockable is said to be available to all players by simply progressing in the game.
The entire storyline of Fable Legends will be available to all players, along with any additional quests added to the game in the future. Heroes, and Villain creatures, will be added to the game periodically too, which will also be available to everyone.
The game will function like some other free-to-play games, such as League of Legends, for example, by using in-game currency - Silver - which is used to buy in-game items. Of course there will also be the ability to buy in-game gold with real cash, which can then be used to buy in-game items also.
A rotation system will be incorporated for the game's Heroes. At any one time there will be four heroes available for everyone to play for free - if you like a certain hero you can unlock them for use whenever you like by using silver or gold to buy them.
For Villains, players will be able to use the in-game silver and gold to purchase allegiances with different creatures for use in quests, along with traps too.
Take a look at the Fable Legends Free to Play announcement video below, to see some in-game footage, and also hear from David Eckelberry.
Fable Legends will live or die based upon how much real money players spend on the in-game gold, and of course that will depend on how fun the game is to play. The new free-to-play model could work for the game - I play a lot of Dota 2 (which is also free-to-play), and sometimes I splash out on a few in-game items here and there; one, because I want to make my heroes look cool; and two, because it feels good to support a game I get so much enjoyment from for nothing. Good luck to Lionhead Studios with this bold payment model, let's hope it works out for them.