The allegedly leaked part that this rendering is based on has already been thoroughly debunked as being made by the company showing off the part. They made it as an ad for their company, probably in order to get a Samsung contract. If you read through that other topic, you'll see people pointing out plenty of evidence, plus showing clearly ETrade Supply's motivations for making their video.
It's a very good knock-off, mind you, but flawed enough as to show it was not made by an Apple supplier, and logically there's no way they could have gotten a legitimate part, anyway. The company that produced the video is quite capable of manufacturing such a part. They have the equipment and expertise, and one of their guys is a genius of viral marketing to come up with the hoax. Apple's competitors read Apple rumor sites too, and something like this is a perfect way to get your part manufacturing company some attention.
That is not to say Apple is or is not working on an iPhone of this form factor, or that it will or will not look like this, just that the part itself that's been shown around on the internet recently is a fake produced by ETrade Supply. Whether they made it themselves based on the alleged blueprints, or they made those blueprints themselves and leaked it earlier so their video would be better received, is unknown.
The thing to remember is that Apple makes prototypes of all sorts and sizes. They covered a table with prototypes way back when the iPhone was just being developed, and played around with them before deciding on the 3.5" size we know and love, debuted with the iPhone 1. It's possible Apple made a 4" taller iPhone recently, and rejected it, but the designs or parts ended up walking out of the building, causing people to think it's actual the iPhone 6. Really, it could just be a rejected design. It could also be a design by Apple intended to confuse their competitors, leaked now to disrupt competitor launches, or cause competitors to spend money copying Apple's fake design.
Nonetheless, this rendering is based on a part produced by ETrade Supply as a way of getting attention to their company, not a real part from an Apple supplier or Apple R&D. Whether that fake part is based on a real part is unknown. Whether Apple is actually making or has experimented with an iPhone of this design is also unknown. Until we start seeing legitimate parts from legitimate sources, such as the recent iPad part leaks, we won't really have any idea whatsoever.
If you like the design, don't get your hopes up. If you hate the design, don't get so worried. Apple won't be announcing the iPhone 6 for another few months yet, and genuine part leaks won't happen until much closer to October when production ramps up.
Right now this is all just one big rumor circlejerk, where sites copy speculation and hoaxes from each other, creating the appearance of multiple reliable sources instead of one game of
Telephone. If I remember right, this all started from one rumor site merely speculating how Apple could make a 4" iPhone, without ruining the established retina PPI. From there, a few more sites posted that speculation as news, and speculated further. A few weeks pass, and somebody makes a blueprint based on that speculation and some rumors, posting it as a legitimate blueprint. A few more weeks pass, and people with the equipment, expertise, and financial incentive to do so build a fake part and pass it off as "maybe real", with their logo and company name plastered all over. Now we're in the computer generated 3D model phase of the circlejerk. All because one tech writer speculated on how Apple might pull off something they've always said they won't do.
exactly my thoughts, people just don't get 
