My fascination with Fallout 3 was mostly because I'd never played a game where my decisions actually impacted the world around me. I could kill off NPCs, blow up whole towns, make and break alliances and so forth.
All of this stuff opened and closed doors and questlines as I played through, and I found it all to be relatively organic. Up until then, most of the RPGs I'd played didn't allow for that kind of drastic alteration to the landscape so I was naturally sucked in.
I am also a huge fan of dystopian/post-apocalyptic fiction and I loved Fallout 3's interpretation of America after a nuclear war. There is nothing so haunting as a touch of the familiar in your wasteland. I also liked the music choices. Gave the game a really odd retro feel that is hard to get right. But Bethesda, in my opinion, did it.
New Vegas didn't really grab me the same way and I never finished it.
I tried Oblivion and just couldn't get into it.
I am going to be picking up the Legendary Edition of Skyrim for PC and I'll be applying the hi-res mod to it. I've heard there are all kinds of insane Skyrim mods that make the game a completely unique experience if you put them all in. Starvation rules, extreme temperature/environmental conditions, and all other kinds of challenges that a person might actually have to deal with in a world like that.
I normally don't like 'real life' in my fantasy games, but I have to admit that the community modding culture of Skyrim has me very interested to give it a try.
