Being quite a rabid fallout-fan, i agree with all other comments that point out the lack of RPG elements in this game.
In spite of not being a true rpg, this game is huge because of its fight-mechanics. I never played a game that give as much possibilities in "tactics" (i suppose that's why it's called a tactical RPG). You can really make ambushes, infiltration, frontal assault, sniping ... in a far better way than any FPS ever made (IMHO). For more, if you consider the tons of avaiabale guns, there is many ways to play the game.
The last important thing i wish to say is that the multiplayer mode can be very enjoyable if you can play with fairplay guys you know well (i.e. guys with who you can agree on extra rules before playing), despite the fact that "skirmish" is the most interesting.