From the PlanetXbox360.com feature article:
"It's time for the fifth release of downloadable content for Fallout 3. Mothership Zeta is reportedly the final DLC pack for the popular title and takes players through a journey that is literally out of this world. This journey involves aliens, space and the whole sci-fiction shebang. So the question remains, has Bethesda delivered an epic quest worthy of returning to the world of Fallout 3? Or does it fizzle out faster than soda pop? In comparison to the previous Fallout 3 add-ons, Mothership Zeta is among the shorter of the bunch."