When you truly immerse yourself in the world, and play on [Very hard/hardcore], It truly is, glorious.
So, the story can hold its own, step up from F3 yeah... but how's the gameplay? From the trailers it looks pretty goddamn similar, well you're WRONG!, the combat is a lot more solid and fluid, considering this time around you can actually aim down sights, lot of people don't really like that, but there just a bunch of assholes stuck in the past. this time around crafting plays a big role in combat, heres a few things you can "craft" to help out in combat [bombs, grenades, weapons, ammo, poison's, even guns in some cases], but other than that the combat is similar, you point, shoot, and occasionally V.A.T.S, which is when you can basically stop combat, and depending on your skills/perks, you can shoot certain limbs to damage em and or shoot em, if you can hit em.
Overall, this is the game I spent the most time on, Definitely worth it, just make sure your PC can run itl