So the new DLC is called "Agents of Change" (info from http://www.platformnation.com/2011/05/29/details-for-brinks-agents-of-change-dlc-announced/)

It has two new maps, two new outfits (one for security, one for resistance), five new abilities, level cap at 24 and two new weapon attachments.

The maps are Founders Tower and Labs. Fight in the Founders Tower and in an underwater laboratory.
The new outfits are The Sad Punk and The Lemmy. A steam punk outfit for resistance and a European police officer inspired security outfit.
The abilities are a UAV for operatives, napalm grenade for solider, fire mine for engineer, field regen unit for medics that increase the health regeneration of any nearby teammates, and a tactical scanner for the universal abilities that show you the buffs of enemies.
And the the new weapon attachments are a bayonet and a weapon shield.

All sound great and come out soon in early June. If you play PSN I'll see you on the battlefields. PSN ID is same as my posting name.