Once upon a time, I had a lot of fun playing Railroad Tycoon for the Dreamcast. My roommates and I played it together, one person on the gamepad while the others offered advice on where to lay track, what cargo to carry, etc. “Train Frontier Express” (TFE) brings that back, but in a slightly different form. Borrowing more inspiration from roller coaster simulations than it does from Railroad Tycoon, TFE is broken into two parts: building your railroad (and the entire world around it), and riding it. Best of all, the developer has been aggressively updating it since its August release with bug fixes and new content and, as of this writing, the game is now on third release in six months.
One of the big features added via an update were online modes for up to 4 players (including online co-op). The idea of building your model railroad world together with up to 3 others through the online modes has the potential to appeal to the Minecraft crowd, but with the added benefit of a bit of inherent structure (railroads work a given way, after all, you won’t put one up a steep mountainside).
“Train Frontier Express”‘s 240 Microsoft Point asking price is a damn sight cheaper than Railroad Tycoon was, let alone a big train set. Model railroading is a very popular hobby, and gamifying it brings it potentially to a much bigger audience. Using a controller is not as elegant as a keyboard and mouse, but the developers have done a fantastic job under the circumstances (the interface is definitely nicer than Railroad Tycoon on the Dreamcast). All in all, very much worth the price if you’re even casually interested in trains and/or model railroading.
Here’s what the developer (Team Train Frontier) has to say about the game:
“Train Frontier is a landscape building and train riding good time. Make an epic creation, then share it with your friends through Xbox Live and ride together. Build it, share it, ride it, crash it, relax!”
Writings of Mass Deduction 
It’s really very well done, considering how difficult simulation/management games can be to implement on a console.
What’s most impressive to me about Train Frontier Express is how it’s not only good, it’s rapidly getting better with strong post-release updates. There are so many indie games that are close to brilliance, but never get that one niggling detail they need corrected to get there, that it’s wonderful to see a great game/sim becoming greater.
It’s encouraging to see an Xbox indie game getting continuing attention from its developer and, as you say, it’s particularly gratifying when the game was already a good one.