Hart’s Deep is a very large project we’re working on, introducing a new, mostly self-contained game-system neutral campaign area to be used for a complete adventure path, taking a group of d20 characters from 1st level all the way through 30th. The book on Hart’s Deep would be sold as-is, with the d20 stats available separately to those who had purchased the book, with broader descriptions of areas available for purchase separately, and the adventures sold both individually and as a subscription, receiving each adventure in a specific timeframe.
Since then, however, plans have changed somewhat. We have decided to add the FATE system into the mix, and provide stats for Hart’s Deep in both in some flavor of D&D and FATE, plus FATE stats for the adventures. The FATE version will contain certain rules elements and information specific to FATE, including suggested Aspects, new race information, and stats for the various groups in Hart’s Deep, as well as stats for the city itself.
Work on Hart’s Deep, through examples and worldbuilding discussions, has been posted at Lisa Hartjes’ blog. We invite you to go and check it out if you’re interested in the city, or in worldbuilding in general.