Trainmaster Train Simulator (TMTS) was on the burner, but when the real railroads wanted to convert the program into a training program for them the company went into full progress to meet the demands and gain some quick and big dollars.
Kuju and EA are teaming up to provide Kuju Rail Simulator (KRS) that will be distributed probably in 2007. Kuju was the company that really did all the work for Microsoft in developing MSTS.
You can find more info at the message forum at train-sim.com.
Bob Edwards