The free 'Agents of Change' DLC for Brink will arrive on August 3 on Xbox Live and Steam and the following day on PSN.
As long as you download Agents of Change during the first two weeks it becomes available you'll be able to play it for free forever.
Achievements and Trophies for the DLC are detailed below. Have a look at the Agents of Change announcement for more details on the DLC.
Bethesda's also put out a bunch of new DLC screenshots, which you can see at the bottom of the page.
Science Maven:
Win Labs as both factions in Campaign Mode
50G Bronze
Towering Achievement:
Win Founders' Tower as both factions in Campaign Mode
50G Bronze
A Burning Thing:
Kill an enemy with a Napalm Grenade
20G Bronze
Pyromancer:
Kill an enemy with a Pyro Mine
20G Bronze
Remote Control:
Kill an enemy with a UAV
20G Bronze
Mutual Support:
Have a Field Regen Unit buff more than 3 players simultaneously
30G Silver
Ark King:
Reach Level 24
60G Gold