BioShock 2 used to run through the loathed Games For Windows Live. Now that Microsoft's service is done for, though, the game's Steam version has just been updated. And what an awesome job they've done.
Canadian studio Digital Extremes (Darkness II, Dark Sector), who originally handled the multiplayer for the PC version of the game, have rolled up their sleeves and made a bunch of changes, updates and additions for the occasion, going way above what would have been expected.
The game now has more streamlined matchmaking for multiplayer. It supports the Xbox 360 controller. It's got Steam achievements. The process of levelling up in multiplayer is now "quicker and easier".
That's not the best part though. The best part is that if you already bought the game through GFWL, you can use the same activation key in Steam, and doing so won't just unlock the Steam version, it'll get you all the game's DLC, including the Minerva's Den singleplayer expansion.