[Junkface]

I think it's a mistake to equate writing with story. The story is pretty much the sequence of events in the game, the premise, and I guess to some extent the characters whereas writing is concerned primarily with the use of language.

I personally revile all this emphasis on storytelling and view the story as just one small part of a larger palette (including visual style, audio design, game rules, puzzles, game environment, writing, etc) a game designer may use to express his vision. As such, the story isn't something I particularly notice, unless it's glaringly inadequate, so I can't comment on the relative quality of stories in adventure games.

Tim Schafer's games, particularly Grim Fandango, are the obvious examples of great adventure game writing. In Grim Fandango what distinguishes the writing is its wit, the way it provides effective characterisation without being obvious or unnatural (see: The Longest Journey, and to a lesser extent, early in Dreamfall for examples of what not to do here) and most importantly, and most difficult to give an example of or explain, the general elegant use of language.

As for cutscenes (which even Schafer is guilty of overusing, though unlike a lot of designers I think he realises it's a problem), I wish they were wiped out completely. At worst they just demonstrate the failed movie director complex so many designers seem to have, and at best still come across are a lazy way of moving the game forward or providing the player with a reward. I should clarify that by cutscenes I mean entirely non-interactive sequences, like intro and ending movies; there may still be a place for short scripted events (e.g. Call of Duty, Half-Life, even if they could be refined a fair bit) or what I call "interactive cutscenes", the only example of which I can think of is Bone: The Great Cow Race's dream sequence, which I thought was done in quite a novel way.