First of all experiment looks into hypothetical case of scientist who studies physical appearance of colors. As soon as color perception by woman eye involves so many factors like the light reflection from the color itself and the wave length of this light – there is no chance it would be possible on the black and white Mary’s world.
Furthermore appearing of the red apple to the scientist by accident – how can be sure it is red she seeing if she spent entire life surrounded by black and white? As a person who studied all physical facts about the colors she would know that apples may appear in several colors.
Also there is a common knowledge that the people who had eye surgery and experienced seeing world around them could be extremely overwhelmed and shocked. the same effect the colourful apple should have on the scientist.
Finally but not lastly emotional side of the “experiment” could have pretty positive effect: it might help to understand connection of human psyche to colors: develop more researches on how exactly color and it’s shape could positively and negatively affect our daily life.