After months of running an Open Beta on Steam, Relic has finished migrating all multiplayer and achievements from Games For Windows Live for Dawn of War II and Dawn Of War II: Chaos Rising to Steam. It is worth noting Dawn of War II: Retribution already launched using Steamworks in 2011, sans GFWL.
Relic posted this to the Steam forums, and goes on to explain what went into this, and you can read the rest of it here: http://steamcommunity.com/app/15620/discussions/0/616187203953578017/
As a studio, we are very excited to illustrate our commitment to the Dawn of War Franchise. Now having re-launched Dawn of War 2, we are looking forward to new and old fans alike experiencing this exciting universe!
Re-launching older titles is always an interesting and difficult task, and as technology advances and focus shifts it is inevitable that changes need to be made. We wanted to take a moment to sit down and let our community know exactly how the Dawn of War 2 landscape will be changing.
The most recent changelogs will be updated here: http://steamcommunity.com/app/15620/discussions/0/616187203947612034/
UPDATE: 9/4/2014 11:20am PST
2.6.10216: Dawn of War 2
• LAN / Direct Connect.
• Referee Mode.
• Ability to “Pause” during multiplayer.
• Games For Windows Live Removed.
• Previously Dawn of War II and Chaos Rising Shared the same Leaderboards & Achievements. These have now been separated per title and using Relic Servers.
• Relic Battle Servers integrated to manage multiplayer networking.