yeah i know what you mean, The Crew was one that looked great, turns out it gets boring real fast if your mates don't play it with you.
i've enjoyed both Fallout 3 and New Vegas, while i prefer Fallout 3 as my top game, New Vegas is the one i prefer playing for some reason, New Vegas did several things that i like, such as weapon mods and ammo benches, but they also missed out on a few thing, the custom weapons being my main gripe with it.
Fallout 4 looks great for sure but i'm reserving judgement until i play it (Fallout 3 is my #1 with New Vegas being #2) there are afew things i like such as settlements and the crazy amount of mods for weapons and armor, however i have a concern they may have gone for too much too quickly and it may take away from the for game.
what will make it of break it for me is the main story line, FO3's was really good, NV's was lacking abit imo, i liek the options the games give you but i think NV just gave you too many, there needs to be some linearity to the story imo more so for a game such as this that has an extensive Lore behind it.
in any case i'm looking forward to playing it in november, if its going to be worth the wait (game been worked of like 7 years or something stupid) is a question that will remain unanswered until then. its a bit annoying that we don't know anything about the story line, other than your character somehow survived 200 years in a vault and no one else did.