A different style of experience, but still Fallout 3.
Operation: Anchorage is an interesting bit of DLC that is throw onto the side of the Fallout 3 story. You can access the content at virtually any time by going to the aid of the distress beacon that is activated in the capital wasteland.
Basically, some Brotherhood Outcasts want to get to some phat loot, but they cannot because they do not have the proper computer to access a simulation program that will unlock the armory. Conveniently, your Pip-Boy can do this and you get tossed into a pre-war simulation of an American raid on Anchorage, Alaska after the Chinese invaded it.
The Matrix-style premise leads to a nice, snowy environment and an interesting setup for execution. You are in a simulation, therefore a lot of things act differently. Enemies melt away when killed, and ammo and health can be repaired at certain stations throughout your mission. Most importantly, if you die in the sim, you are dead for real.
The mission itself feels a lot like a Call of Duty mission. Something in it gave me a feel of Goldeneye for the N64. You will be using standard weapons in general. However there is a pretty neat Gauss Rifle in Anchorage that you will definitely enjoy. The mission is rather long, but is nicely broken into what could be perceived as five smaller missions. You cannot stop the sim once you start, however, so (like some other Fallout DLC) you have to complete it all in one go.
The after effects on you Fallout game are somewhat small, however, and this could be somewhat saddening. You will get a small handful of new weapons and armor that you couldn't otherwise access in the Fallout world. So, once the content is done, you only have a small collection of mementos to take with you back to your game.
Operation: Anchorage is a fun and entertaining addition to the Fallout experience, but some of it feels like it doesn't quite belong and very little matters once you leave the simulation.