Among the other titles of Bethesda that uses Steamworks (like Skyrim & Rage), the upcoming Dishonored game that will release this October will be using Steamworks as well.
With Dishonored now using Steamworks, we can expect achievements, matchmaking, and many other features for the PC. We should have our hands-on impression early this June when E3 officially starts.
Dishonored is scheduled for release this October 9th on the Xbox 360, PlayStation 3, and PC.