That's funny, I stumbled upon this forum while looking for discussions on that game. I have only been playing it for a week or so, but it is a fun game. It is very easy to pick up and play, spending 15 minutes to do the tutorial will teach you just about all that you need to know. As far as I have seen, it is not a very deep sim game. You connect the cities with rails, and set up your trains' schedules and payloads, filling the supply and demand for each location. There is no building involved... you drag and drop track, and the cities grow around it. There is no placing buildings or landscape, it just happens as you go.
IMO, the game is simple to learn, and not much harder to master, but a fun way to spend some game-time. Throw on some tunes and fulfill LA's demand for gold, and Detroit's demand for power, good times.