I think, we all know that a good storyline makes a better game. If a game can catch our emotions when we play, doesn't it make us want to continue? Having a story to a game, for me, makes it feel much more personalised, and individual. ... I know there are probably hundreds of games with similar story lines, but the character choices set some apart from the rest.
Now don't get me wrong, I don't always go for a game with a good storyline. I'm a bit of a fan of mindless violence and decapitation, but those games are more of a group thing really... Not the same affect when your sat at home blasting the insides out of computer played characters, to when your getting head shots against your friends characters! Example; in college, we used to have random massacres on Unreal Tournament when we'd finished an assignment and had free time... Or, just when our tutor left the room... fire it up for a quick bloodbath... Anyway, I'm getting side tracked! Back to the point... ^^;
As a player, does the story happen to you? Or do you make the story? Erm... Well, the games programmed with a story, so I'll go with the first. Unless it's like World of Warcraft. WHICH I DON'T PLAY.. I might like to point out. But my ears are forever being traumatised with the endless storys of Saphyr, one of Donna's World of Warcraft characters... She gets very into the whole "role play" thing, and has created storys in the game for her. Which, alot of Warcraft players probably do... I don't get the attraction really..
Second Life? Never heard of it.. So I don't know the story, can't answer that. And I have yet to play Call of Duty 4! Yey for expencive "next gen" consoles... But the rest of them follow the life of a certain soldier, no? So... is the story not about that guy's experiences and losses in a war, I 'spose saying it's a war story is going along the right lines.
...Although, thinking about it... I think that Unreal is pretty much the only game I've played without a story. Kingdom Hearts is the story of a boy searching for his lost friends and defeating the heartless taking over O.o Persona 3 is that of a boys battles to defeat Shadows, and of the friends he makes around him, and I'll not go into anymore detail, or I shall be rambling for days to come, and I don't have that energy ;3
So yeah, in my personal opinion, the story is almost as good as pretty characters, and colourfulness!