MacBook Pro :: How To Exchange Products

I bought a macbook pro about 3-4 months ago. I posted before with problems, though it's getting much worse. Initially the "return" key stuck pretty badly. I brought it into the genius bar and they claimed they didn't feel it (it's very very obvious, they clearly just didn't want to deal with it).

Anyways, a month after that the computer began rattling. Ever once in a while it would make a prolonged and negative sound. When I pick it up nowdays it sometimes makes a suspicious sound as though something is moving freely inside.

And finally, another month later and two hours ago, the battery failed. It now only runs when plugged into the adapter, and its status is "service battery" in the little icon thing.

At this point I really feel the computer should be traded out; too much is going wrong for a mere fix (and the genius bar has been very stubborn with me in terms of admitting problems). So, symptoms in mind, do you think I should be able to trade in my mac, and how would I go about doing this?