Not surprising. I'm sure Apple builds dozens of working prototypes. The million dollar question is: which one(s) will make it into production?

At this point in their product lifecycle, a decision has probably already been made. It takes months to ramp up and prep the hardware component suppliers....so with an anticipated June kickoff date, Apple will need to start building these by the beginning of May.

Given how fast one can type on an iPhone keyboard it seems extremely unlikely that Apple would spend any energy on such a project.

Make that 4 models. I hear they are working on one that uses a stylus as well.

Apple has implied that they often put out many different prototypes with unique features specific to each vendor that is a candidate to build that one specific prototype to weed-out leaks in the supply chain.

I doubt Apple would ever seriously consider a slide-out keyboard. It's not their style. That's not to say that Apple would not submit that request to vendor "A" to see if they can keep their mouth shut.

According to "clip die" tomb said to me

The real translation is

According to Steve Jobs, who said to me in my dream

As the pixel size of the camera,

The rear camera will also be provided by OmniVision. There are two choices: 8M-pixel and 12M-pixel cameras. Because using 12M-pixel memory consumes a lot of memory and is slow to upload to cloud devices like Facebook. Due to business considerations, it will lean more to 8M-pixel camera.

a fifth prototype was said to have a mouse.

Instead of a slide out keyboard why not a slide out gamepad?

A 6th prototype had a rotary dial.

A slide out keyboard would be interesting to see considering one of the things that many detractors say is that they wouldn't buy it (or any smart phone) without a physical keyboard. If they were able to keep it the same thickness and include a physical keyboard, I might jump on it as an option. I don't know how many times typing in landscape mode has been a pain in the butt because most of the screen real-estate gets absorbed by the keyboard.

It might not be their style, but the more I think about it, the more I might like it (especially with the option of switching between the on screen and physical keyboard). Now if we could add a rotary dial....