Of course the game lives on the dialogs, puzzles and jokes
in the long run, its also about "imersion".
So then I have a nice graphical style, I feel like beeing in the game.
If I get put of by stupid Art all the time, I cant enjoy
the game itself.
And playing any Monkey Island, I will automatically
think of the very first game, and how the
world was presented.
So it probably works for (most Kids now) people that
never played the old games.

A similar thing was with Gothic 3. They changed a lot,
and a lot to the worse in my eyes.
Although beeing a big fan of Gothic (1+2+addon), I never
finished the third game. I just never felt like beeing in
that gameworld again.

Fallout 3 could have been the same error.
But fortunately, although much different to the originals,
its a cool game by itself.