What a great game. I just finished the main story last night and have a great sense of satisfaction and money well spent. I am extremely disappointed that you CANNOT continue your game in the world after the final quest, so I have to go back to a previous save now to do all the side quests I missed.
The game was very similar to Oblivion, but many times better. In Oblivion I could travel for miles wandering around and not meet anybody and not be bothered, but here in Fallout 3 every step I felt there was something around the corner. I stepped with a real fear that something would jump out on me. I think the cause of that was the post-nuclear-bomb setting. The ruins, the desolate buildings and burned out cars, I was always moving with excitement and intrepidation about what was coming next. Even in areas I had been before and killed all enemy, I felt like something else was around the corner.
Graphically it looks fantastic but I did have a few issues with tearing at times and a few framerate drops. The most annoying thing though was that quite often after saving or fast travelling I would lose my hotkey settings for weapons so had to keep re-assigning them. An annoyance but at least I had no crashes or game killing bugs.
Fallout 3 for me is definitely a candidate for Game of the Year, I think the only one that can beat this now is Call of Duty: World at War, we will see about that one next week.