Matthew
I think that it is necessary that this movie has a realistic look to it rather than a cartoon look. A more realistic look will fit in far better with its live action predecessors than a cartoon look. I also think that it is important for Ghostbusters to actually have a scary side to it. The scene in the New York Public library? The scene where the hands grab Dana from the couch? etc etc I just don't think the scares which are so important in Ghostbusters can be acheived if the film is given a cartoon look.
I have one word for you, Matthew: VERISIMILITUDE. The movie needs to look like real life, but exaggerated slightly.