Chris Avellone, senior designer on Fallout: New Vegas at Obsidian Entertainment has written up a blog post on video game writing v. writing. Read on:
Do you feel that video game writing, and video game story creation differ from other forms of creative writing? If so, how?
Yes, especially for RPGs, because reactivity usually requires you to tell the "story" out of sequence - and usually you have to tell several stories at once depending on how many branches you provide.
In general, though, it's better to approach it from the game mechanics standpoint and let what the player can doFallout's good about this - some of the best "stories" I got from Fallout 1 and 2, for example, were ones where Stealth and Combat options spoke for themselves in reactivity and quest solutions. And a lot of child pickpockets got blown up from ticking dynamite that somehow got planted on them - or through accidental repeated injections of Super Stimpaks.
In short, the game "story" can end up being less important than the player's experience in the game, whether they are actual story events are not. It's hard to compete with a story about how a player's 3rd level dwarven fighter survived a bum-rush of 20 orcs in a narrow corridor armed only with a ball-peen hammer and smashed through them Oldboy-style with only 2 hit points to spare... and it's guaranteed to generate more passion from the player than perhaps your most tragic character with his heart-rending story to tell. It's something you just have to accept, and even better, provide opportunities for. Give the player room to breathe.
Creative writing also carries with it the danger of subjecting the player to the story - TV, film, novels, short stories, and comics demand a more passive absorption by the reader/viewer than video games should, in my opinion - like System Shock 2, BioShock, etc. you want to give the players the freedom to move around the game world and interact with it without being forced to watch cut-scenes or be paralyzed in place to watch events play out, you need to allow for the player to interact with the experience. One could argue Breen's broadcasts in Half-Life 2 and the recordings in BioShock are technically passive absorption experiences, but they allow the player to interact with the environment and control their field of view while they're taking place - you aren't forced to absorb them.
Also, one other important factor in game writing is details - you have to be specific in game writing, especially in organizing and scripting NPC knowledge. You need to be able to track quest states, how much an NPC knows about you, about a quest line, and about the world at any one time. You have to know what happened to X NPC at Y time and if it affects Z quest. Can you have done Z before talking to X? What if the player kills X and then stumbles across Z? Etc, etc. in the game tell a story.