Fallout: New Vegas is essentially a big choose-your-own-adventure platform with several major choices of varying mutual exclusivity. The real heart and soul of FNV, though, is in the incidental stories found in side quests and companion quests--while they are rarely necessary to "win the game" (i.e., trigger the credits screen), they are often more compelling than the major quests (find the MacGuffin and pick A, B, C, or D) and allow much greater opportunity for forming the player character. I'm not sure that you'll find the total storytelling better than that of a good or great book, but I think New Vegas still leverages the type of narration that is unique (but not guaranteed) by video games.
edit: Just remembered that Planescape Torment was created by Black Isle, the studio that also worked on the first two Fallout games. Black Isle later dissolved, but the key players later formed Obsidian, the studio that developed New Vegas on Bethesda's behalf. I imagine it's very likely you've already played FNV (in which case, I'd love to hear how your experience aligns with mine), but if not, it's probably up your alley.
I, on the other hand, found it very lackluster. Most of the game's environments are filled with identical copy-paste monsters, it's almost entirely lacking all the incidental background quests and character material that make even the "bad" Fallout games feel like there's something new around every corner, and the game very visibly gets a simpler, less player-driven narrative as you go to each new world.
The 'side quest' side of all fallout games is usually far stronger and more interesting/rewarding for sure than the main trail which I think is almost deliberately made flat/weak to encourage you to explore the world more. The really good ones I think are the stories you piece together from terminal entries, particularly those in vaults (Vault 11!).
They all right. I think there is some nostalgia goggles there, same with Planescape: Torment.
Decent writing, for a game, but the isometric view isn't great and the gameplay is clunky. Plot and theme-wise it holds together better than Fallout 3 -- which has plot holes so big you can drive a bus through them -- but FO3 was a lot more fun to play, at least the first 2-3 playthroughs, and has so many freakin mods it's a different game.
edit: Just remembered that Planescape Torment was created by Black Isle, the studio that also worked on the first two Fallout games. Black Isle later dissolved, but the key players later formed Obsidian, the studio that developed New Vegas on Bethesda's behalf. I imagine it's very likely you've already played FNV (in which case, I'd love to hear how your experience aligns with mine), but if not, it's probably up your alley.