Yeah, it was poorly executed and not repeated with Mass Effect 2. They built something into the Mass Effect 2 called the Cerberus Network, which is a DLC hub that exists in the main menu. Basically, you can download stuff from there and when you load your save file, it appears in the main game. The first DLC is free, which includes a little side mission and a completely new character.
Dragon Age attempted something similar, but also had DLC you had to pay for at launch (in addition to the free party member). It was a disaster. Then a month later they announced a $40 expansion. Totally lame.