NOT a RPG, and NOT a Fallout game!
Fallout 1 and 2 were considerably successful CRPGs (Computer Role-Playing Games) back in the 90s, a time when some quality and diversity still existed in the video gaming scene.
That was before the tidal wave of copycat 3D engine FPS (First_Person Shooter) games poisoned this market and brought it to the sad, sterile, unimaginative status quo it is today.
99% of today's games are no longer made with love, imagination and dedication. They're just another corporate product, exactly the same as fast food, same taste applying. A reflection of today's entertainment industry in general (Hollywood, and so on). The number of quality, intelligent, mature games today can be counted by the fingers of one hand, and this so-called "Fallout" 3 isn't one of them.
"Fallout" 3 is a cash-in in the name of an honorable, respectable series of RPGs. Now it's just another 3D FPS arcade shoot-em-up, all flashy and noisy and filled with an aura of hype courtesy of a nice marketing campaign and a batch of corporate-endorsed reviews which all say the same and give virtually the same exact score to each and every game, but devoid of any real substance.
The dialogue, one of the three key factors in any quality RPG, is adequate for the next Aliens Vs Predator movie. The world depth and detail, the second of three key factors in any quality RPG, is about the same level as the average Gameboy title. And the combat system, the third and last key factor in any quality RPG, has as much to do with a RPG as Quake and Doom do.
Don't get me wrong: "Fallout" 3 can be looked at as a cool little game if you're looking for another 3D FPS and you ran tired of Far Cry, COD, Crysis, etc. But it's not a RPG nor does it have anything resembling of intelligent, mature gameplay, and if that is what you're looking for, you better save yourself valuable time and money and start looking elsewhere now.