Call me old, but I loved the original C&C and Red Alert cutscenes/storylines. Following that, Assassin's Creed, last two Batman games, Half Life series, Halo, Jet Set Radio Future, Skyrim (Elder Scroll Series in general), Freelancer/Starlancer, Homeworld, World in Conflict, Diablo series, FEAR, Starcraft, Thief, Portal 1 + 2, Deadspace. Just a number of games that came to mind from reading "What games had best storylines..."