Steam News announces that BioShock 2 is now available on Steam as a bundle with all its available multiplayer DLC and the single-player Protector Trials pack, with the shooter sequel collection carrying a 50% discount for the next few days. They state a new update has removed the reviled Games for Windows LIVE service from the game, and that previous owners of the game are entitled to a complimentary Steam key. Here's a BioShock 2 Steamworks Update FAQ and here's word:

In August, the Games For Windows LIVE service marketplace closed and some of you wondered what would happen to BioShock 2 on PC. We remain committed to supporting BioShock 2 on PC and are excited to announce that starting today the game is available via Steam. Not only that, but the Steam version of BioShock 2 includes all available multiplayer downloadable content, as well as the single player “Protector Trials” DLC!

With the help of our friends at Digital Extremes, BioShock 2 on Steam fully supports popular features of the platform, including controller compatibility, Steam achievements, and Big Picture mode. Matchmaking is easier than ever now, allowing you to search for “any game,” as opposed to having to select your game mode. Leveling up is also quicker and easier, as we’ve fine-tuned the multiplayer experience to be better than ever.

If you have already purchased BioShock 2 through a different digital partner, we’ve got you covered. Simply take the same game activation key you already own and “activate” it within Steam. Doing this will grant you access to BioShock 2, all of its multiplayer and Protector Trials DLC, as well as Minerva’s Den – the single player story-driven add-on that includes new weapons, enemies, and plasmids!