I'm still wondering whether it will be included for people who already bought the main game or preordered it. They suggested it would be previously, but everything points towards it being a paid DLC for everyone.
From what I understand everybody will have to buy it. Of course it’s nice to get things for free (especially if they previously stated it would be). But if it’s good DLC rich of content I don’t mind paying. It was the same for me with the two expansion sized DLCs in the Witcher 3.