This isn't the iPhone 5. But it wouldn't surprise me if, come this fall, it looks very similar to this prototype created by Antoine Brieux. It feels to me like a natural evolution. Check the gallery.
Apart from making the next generation iPhone a piece of pure glass, this seems like the most logical way to further simplify the current design: One single body of metal encasing the electronics, sandwiched by two slices of curved glass.
That said, I wouldn't like it to look like this. Perhaps only without the glass back, leaving the pure metal, and flushing the glass with the stainless steel body on the front.
But pretty, in any case. Thanks for the renders, Antoine Brieux from NAK Studio.