ION Storm's John Romero wrote a post on the PlanetDaikatana forum addressing a series of questions regarding his first-person shoooter, as it is nearing the end of its three-year development span (thanks Stomped). There are several details about the game's content and features, as well as this bit about their post-release plans:

We will be splitting the one team into two teams. The bigger team will be working on a Fifth Daikatana Episode, marketed as a mission pack. We will start working on our next big game after finishing the 5th episode.