ok, the same exact thing happened to me. Dropped the phone, dented the upper right hand corner, subsequently shed a tear every time i would look at it afterward.
I decided I had enough and called 1800MYAPPLE and explained my situation. The customer service lady then proceeded to tell me that APPLE WAS REPLACING PHONES WITH COSMETIC DAMAGE. I was shocked to say the least. I even responded with an idiotic "but it was MY fault! I dropped it!" And she assured me that they would replace them at an apple store. All I had to do was schedule an appointment at the genius bar and they would swap it out for free. Unfortunately there was no appointments available for the entire month, so she told me I can opt for a repair where my phone would be "like new" all I had to do was go through the repair process, free of charge as well. As of right now i received the free loaner iphone they sent me (an 8gb model i might add, nice since i only had the 4gb) and i had sent my phone in for repair in the prepackaged box that they sent. I am unaware of what will happen next but I am sure everything will work out fine and I will be dent-free.
I will update you as my situation progresses. Hope this helped!