Excuse the necromancy -- I was waiting until I had acquired and read REAMDE to respond.
The book has an acknowledgements section at the back, which says nothing about Dwarf Fortress. Although the use of the word "dwarf" in the passage the OP quoted might be a wink.
At any rate, Stephenson doesn't owe anything to Toady. The DF genre was not created by Toady's genius -- it was created because its time had come. The idea of a game where mountains aren't "papier-mâché" has been occurring to people for over half the history of personal computing -- it's just that everyone before Toady has had their dreams crushed by insufficient computing power. Also, DF wasn't itself such a game until the 3-D update.
The time for a real-life T'Rain may come, or it might not. If computing power continues to increase it would be a good bet, but Moore's Law is slowing down and Peak Oil is expected to crash the party.
T'Rain sounds more like a "Minecraft on steroids" than DF. Minecraft at least supports multiplayer, while DF isn't even real time. Sure, Minecraft's underground structure is less diverse and more slapdash that post-3D DF, but that's a shallow detail.
Also, while reading "T'Rain Gazette" news section (on page 167) one candidate, outside the DF genre, for T'Rain's ancestry occurred to me in a flash: EVE Online. The heroes could easily have paid off REAMDE's author and moved on (the ransom was only $73), but were utterly blocked by third parties camping the route to the in-game drop off points in order to steal the ransom payments. That sounds very much like something EVE players would do. I've never played the game, but the brutality of that community is legendary.