Today, Bioware released the first batch of downloadable content for Mass Effect, and I thought I'd just post some of my thoughts on the entire experience for any interested.
The mission can be found in the Exodus System on a X57, a hijacked asteroid that a group of batarian extremists have set on a collision course with Terra Nova, a sprawling human colony. If the asteroid doesn't change course, it will be mass genocide. There's only one person who can save everyone on X57 and Terra Nova, and luckily for us, it's Commander Shepard.
You touch down on X57 in the Mako, with your squad in tow. Right away, it becomes evident what your main objective is: disable the plasma torches that are causing the asteroid to alter it's orbit. It's not a cake-walk, though, as the batarians are well armed and it's pretty clear that they had some pretty serious plans on how to go about doing that: robot drones and attack varren are get thrown at you, as well.
While the action is intense from start to finish, that's not to say that there isn't time for interacting with other characters. There are a few humans who managed to hide away and survive the initial batarian attack. Also, not all of the batarians are behind this genocidal plot, so going guns blazing all of the time may not be the best course of action.
Overall, there is about an hour and a half of gameplay to be had for the $5 admission fee. Everything really comes to a head at the end of the mission and like the most pivotal parts of the main story, this is due to a humanity-changing choice. All things considered, I spent a good few minutes trying to decide what I would choose and how that would effect the Mass Effect universe as a whole. So, all things considered, Bring Down the Sky did exactly what I expected it would: draw me back into it's epic story and help make the wait for Mass Effect 2 just a little easier to handle.