Even before Borderlands has been released Gearbox Software and 2K Games have issued details on the first DLC pack named "Zombie Island of Dr. Ned". It will cost $10 (800 points) and it will be released later this year. It will be the first of many DLC packs for Borderlands according to the developer.
Here is a brief description:
"Tasked with keeping the workers of Jakobs Cove alive, Dr. Ned (who is not related to Dr. Zed from Fyrestone) does his job a little too well, creating zombies and other abominations that now run rampant in this region. Players will have to work alongside Dr. Ned as they embark on a quest to cure the inhabitants of Jakobs Cove in this full-fledged expansion filled with new enemies, new quests and rare loot drops."
And below are the first screens...