On December 2, Nordic Games released a new version of Red Faction: Guerrilla (PC)
for the Steam platform, and it includes a bunch of new features and updates, as well as removing all integration with the Games For Windows Live platform. This means that players will no longer need to sign-in to the game using their Windows Live account for the online portions.
If you already have the GFWL edition, then Steam will automatically add the game to your library, and will also attempt to import any previously existing saved games when it is first loaded. If you don't already own the game, it is currently on sale for around $2.99 USD.
While the updated version of Guerrilla
does indeed have its own set of Steam achievements, it is obviously no longer linked to the relevant Xbox Live achievements, so those who haven't completed this game yet just might be cursing the demise of the GFWL platform.
Thanks to the members of the community that sent this one in!