Bug! was indeed the first of more Sega Saturn games for GameTap. Sega accidentally revealed on their official website that the original NiGHTS Into Dreams will be available on GameTap next year.
The too-early reveal showed a Nights “Behind the Story”. To quote: “Go behind the scenes and get a look at the making of NiGHTS: Journey of Dreams in this exclusive video from GameTap! Learn more about the creation of NiGHTS, the story and philosophy behind the game, and what new surprises are in store for players ready to take their own journey of dreams. Also, make sure to check out GameTap to play an emulated version of the original NiGHTS Into Dreams on your computer!”