If you've been following IGN's coverage of The Darkness, you know that the main character, Jackie Estacado, is taken over by the mysterious powers of The Darkness on his 21st birthday. It may sound strange, but it couldn't come at a better time, as his "Uncle Paulie," (one of New York's powerful mob bosses) decides that the hitman has outlived his usefulness and attempts to have policemen, construction workers and other people on his payroll take out Jackie. All of these efforts culminate in a bomb in a building, which propels Jackie out of a window and into the embrace of the timeless powers of The Darkness, which gives him the ability to gain his revenge on his former mob family.
While IGN went through the opening chase sequence through one of New York's tunnels with Mikey and Nino again (culminating in Nino's beheading and Mikey's crippling via accident shrapnel), they were told that managing to shoot every construction worker in those tunnels would result in an accomplishment for the PS3.
That's significant because, apart from Lair, this is one of the very first titles for the PS3 that's actively acknowledged an accomplishment system (akin to the 360's achievement system) from the start of development. How that might tie into Home's trophy room system is anyone's guess, but we were told that many of the other items that you could unlock would include full Top Cow comic books, cheats and behind the scenes movies with the developers of the game.