I had some VERY light scratches on my phone on the front face, not sure how they got there because I am super careful with my peripherals but never the less it bothered me, don't ask me why but it bothered me very very much.
What I did was I went to the mall and was buying my bumper to get that before they run out and start handing out whatever crap they are going to when they run out of the bumper. I noticed a Ghost Armor stand near the apple store and thought what the hell. I watched them put the full body protection on some other persons iPhone and my fiance mentioned that I had been using InvisibleShield on my old AT&T Fuze and that if I wanted to prevent any future scratches I should try it.
I was hesitant to leave my phone with some random people at a mall stand but went ahead and purchased the full body protection and to my luck there was a 10% discount card that they were handing out I guess because they recently got the iPhone 4 stock, I walked out of the mall given the instructions not to put it in my pocket for a day, not to put it in a bumper or case for 48 hours so I didn't, I went to the lake the next day and basically didn't use my phone due to poor reception.
This is now a week later and I can tell you that I'm completely satisfied, I haven't posted much but so far a couple of my posts have been praising this product and I can recommend it to anyone looking to protect the entire phone as well as eliminate the stupid antenna problem. The best part about it was the ghost armor filled in those scratches so you can't even tell they are there (very very small scratches mind you, no deeper or bigger than a freaking hair). I also use the Waterfield suede pouch with the pocket for my money and credit cards so I don't even carry around a wallet anymore it's quite nice.
TLDR version:
Ghost armor filled in my small scratches, if you're that worried about your scratched phone and you still WANT the iPhone I would advise investing in some sort of fully body protection today and you won't even know the scratches are there tomorrow.
Just my 2 cents as I was in the same boat and I felt so dissapointed in myself for scratching my phone but this resolved my issues and gave me peace of mind with my investment.