Fallout 3 is a game made by the same people who made Elder Scrolls IV: Oblivion and most people would argue about it's quality. To be honest this game has barely set itself apart from their past game Oblivion with the only difference are weapons and setting but the gameplay remains the same, prompting you to ponder if you liked Oblivion. If you did then this is a must buy if not look for something else. In the end you can say it's not Oblivion but you'd be having a hard time not comparing the two given their style of gameplay. It does however still greatly incorporate a good RPG system and a good morality system that affects how NPC's treat you.
Let's start with the graphics. The setting puts you in a post apocalyptic Washington D.C. where almost everything is in ruins. The graphics are great and it is able to set the tone on the feel of an apocalypse where the survivors are either your friend or your enemy it would seem that even the smallest of NPC's have roles due to their alignment of either trying to survive through hard work or trying to survive through others. The charcter designs have been improved compared to that of Oblivion wherein Oblivion looks like they all have round faces maybe even piggish those in Fallout look closer to Human than it did in Oblivion. The main flaw about the graphics is that it's inconsistent, you could be walking at a certain area but due to it's large map scale it sometimes does not allow areas to render themselves right away showing low resolution textures comparable to that of the best Nintendo 64 games.
The gameplay is solid but I stress out that if you played Oblivion then the gameplay is basically the same, so either you liked it or hated it or if you never played it seems like a very slow FPS and or 3rd person shooter in my opinion. The sound quality is quite good, however what brought this down as seen in the fact that due to the number of NPC's everyone sounds the same, other than that from the shooting to the explosions the sound is great.
Fallout 3 is a game that will keep you playing due to it's huge amount of side quests to go along with the main story, and it's scale would make you want to commit to find every location on the map. Although the technical aspects should be improved it is still a buy to most, but if you're a technical loving guy (or a person who dislikes technical issues) be forewarned of it's technical problems that prevent it from using it's full potential.