Neowin reports that today some photos of a prototype with finalized design casing of the iPhone has surfaced in Bangkok. The prototype, which is obviously a fake, is not functioning, but is a "replica prototype" and in his own words, "pretty accurate too."
So we can fall back on what we already know, which is that the unibody case appears to be redesigned to feature an aluminum shell. The glass backing that appeared in the iPhone 4 and iPhone 4S is notably absent; instead, the entire exterior is a single piece. The casing appears to feature the rumored elongated design of the new iPhone, which is said to be around 4 inches in height. Additionally, a new docking port appears to be in place, and the headphone jack has been moved to the bottom of the device similar to Apple's iPod line.
This simply could be a model of the design schematics posted earlier this year, but the evidence of a next generation iPhone having that similar design is getting stronger and stronger.