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I bought a case for mine, my iP4 is absolutely fine, it only had a few fingerprints on its back which don't bother me much.

So yeah, either buy a case or get a screen protector.
 
Screen protectors are not a must. The glass can take most beatings just fine. If you're a paranoid lad, do it, but I've gone without screen protectors for over a year now and found that I was just tossing away my money with them.
 
I went in to Best Buy last night and had them apply an InvisibleShield for me. At first I was not very impressed, it had a few weird looking spots under the film and what not but he told me to wait 24 hours for it to dry. I woke up this morning and it's perfect! All of the bubbles and imperfections are gone and I can barely notice that it's on my phone. It does have an orange peel effect to it but you can only tell if you hold the phone at an angle with the screen off. You can't see the small scratches that were on the screen any more either which is awesome. I give it two thumbs up, a bit expensive for a little piece of film but I suppose the lifetime no questions asked warranty makes it worth it.
 
as far as resale value

People spend $30 on a case $20 on a skin and treat the phone like a newborn child

So people are willingly spending $50 more and not enjoying their phone for a resale value a year- 2 years later ?

Yeah I'll pass and enjoy my phone the way it was intended to be used.

Couldn't have said it better myself. Even if I get $100 less for the phone in resale due to scratches (not likely to be anywhere near that much less), the $50 I lose is WELL worth being able to enjoy the thinnest phone in the world without bulking and uglying it up with a case, and covering its glass screen with a horrible feeling plasticy coating.

By putting a skin and case on your phone, you're runing two of the greatest things about the iPhone!

PS: I just sold my 3G for $20 more than my friend sold his for, and he kept his in a case and skinned all its life. Yes mine had microscratches all over the back (the front still looked brand new!), but who cares!?
 
Gah! Just thought I'd vent. I've been very careful with my phone since release day, especially about putting it in a pocket with keys or change, I always make sure it's in an empty pocket. I pulled it out on the couch today to check a text message and in the lower right corner of the screen there's a series of 10 or so little scratches. :( So much for the Apple store guy telling me not to worry about getting a screen protector because the new glass will never scratch. What an asshat, now I have a scratched screen, even after being super careful about it anyhow.

Are there any known ways to lightly buff the glass? The scratches are not very deep, but they are annoying.

Three mistakes you made:
1) You put it in your pocket. Pockets are the worst and the place where your phone is more than likely to get scratched.

2) You didn't get a screen protector (self explanatory)

3) you listened to the "apple store guy" Common sense would tell you that any glass screen can be scratched.
 
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