I don't know man, it's happened too often that I am certain there's something going on; baddie in my sights and the hot magically misses, and someimes I even see the shot's trail clip right through. Plus why do the weapons and character stats have accuracy ratings? i.e. with the Hunter I can improve accuracy by leveling up certain skills. There's definitely a dice roll going on to calculate the accuracy ratings.
Sure they're both set in wastelands but it's more than just the setting, Que. Fallout 3 is the most recent, but we had Deus Ex, System Shock, Bioshock (though it's more strictly a shooter), S.T.A.L.K.E.R., and technically we can even add Arx Fatalis and Dark Messiah to the list. Borderlands is definitely more of a shooter than Fallout 3 but my point is all these games fit in the same genre (albeit very different settings) and tilt between RPG and shooter.
This is just in the first-person perspective selection, we have other games that fit the criteria but have isometric camera angles i.e. Diablo, Crusader, etc. That's a whole other discussion though.