Acquire is working on a PS2 sequel to Way of the Samurai, called, simply enough, Samurai 2. Like WotS, the sequel will pack a reasonably large area of feudal Japan with characters and events and the anonymous player will be tasked with influencing them as he or she pleases. The developer is promising more enjoyable and diverse sword-fighting with refined tactics and more weapons, but presumably a similar experience system that determines skills in each area. The last one was creditable because it actively discouraged the player from repeating the same moves for eternity.
Samurai 2 is due out in Japan this year, and hopefully someone will snap it up for Western release in the near future, although we're not sure Eidos slept comfortably after taking on the first game, so it might not be them. Whatever happened to "Fresh Games", anyway?