Isn't T9 a commercially available form of this, on a word-by-word basis? Are you trying to find something that is faster than T9, or just an open implementation of a T9-alike?
halley,
My wife kept me awake last night texting her friends and family. Since I couldn't sleep, I began wondering about the algorithm(s) used to make predictive texting work. I decided I would post it as a challenge today since there are several monks that enjoy interesting distractions. I don't have any other purpose for it than that.