From producer's point of view.Emily is the perfect female contestant. She has a very pleasant voice, but without exceptional ability, and her performance repertoire potential is limited.(to really stand out, she will need any song styled and arranged like every other arrangement she has performed this season so far)She *can* sing more challenging songs, but it doesn't suit her or her voice type as well. That makes her ideal in two significant ways.
1) Because Emily is limited, and about as good as Matt but less versatile,it will be easy to keep her in as long as it works , and when the time comes, sooner or later, send her home in a sing off and much of her (young/pop) vote will transfer to the chosen finalist/ideal winner
2)Because she has such a professional polished sound and image, she will be one they can market ,promote and profit off of without her winning
From a purely artistic standpoint,while her voice alone,while beautiful, was not quite enough to make her stand out, I think her dedication and ability to work to her strengths ,not giving up and polishing her act until she made herself stand out is something special in itself, and I hope she gets what she hopes for out of her time on the show.