Relative to what?
Anyway, those who care enough about fashion will remove the case and only put it on when they need a little extra reception. Or, just as likely, they will flock to the third-party vendor who sells micron-thin transparent cases. That vendor is gearing up as we speak.
Or use the headset and put the phone away in your pocket, the way God intended phone calls to be made.
What? I'm not talking to _you_!
They hunch over slightly, and exaggerate the act of speaking into it... visually emphasizing that they're not just casually strolling along talking to themselves.
I know when I'm listening to comedy audio podcasts and can't help laughing, I make sure I'm holding an in-ear bud in place in my ear, or looking at the blank screen of my phone.
We're a silly lot.
In any case, I've dropped my 3GS phone about a half dozen times, twice from 3 feet. No damage so far; maybe some scratches, but I use a matte screen protector (more easily scratched than the glass) and a custom vinyl backing (edges and corners still exposed). There's some dust now behind the screen from the impacts, but a case might not have prevented that anyways.
If I had to put the 3GS in a case, I probably wouldn't have bought it in the first place. But then I prize thinness in phones over other things, since I put the phone in my pocket.
At least the iPhone 4 bumpers are less intrusive and ugly than most 3GS cases. Still a shame to cover the stainless steel edge when they finally brought stainless steel back in the iPhone design.
It also helps, of course, that one's reflexes suddenly become much sharper when one is carrying an expensive piece of hardware. I've made some incredible catches of that phone over the years.
There should be a name for this phenomenon - "the hand of Jobs" or "the reflexive property (of smartphones)", perhaps?