If you look at the current icons for iPhones and iPod touches, you'll notice that they're very similar other than the earpiece and front camera. That's how you recognize if it's an iPhone or iPod touch (earpiece) or if it's the 4th gen or not (front camera).
They all have a similar screen to device ratio and home button.
Now, the iPhone 5 icon is easily distinguishable from all those because of the larger screen and wide home button. It's not the front camera that make it distinguishable from its older version. Then the front camera would have been useless to put on such a small icon given that it's meaningless.
The design of those icons is minimalist, they don't exist to show you the features of the phone, only to make sure the customer knows which version he has before buying an accessory that won't fit. They also haven't put subtle details like the home button icon, the side buttons, sleep/wake-up button, proximity sensors and so on because they just make the icons complicated for no reason and less symmetric which must be a big deal for Apple.
Now that the front camera is standard across all devices, it must also fall in that category.
I believe this is how the iPhone 5 will look like. It's not a generic phone. Apple will always promote their own products through promotional material. I challenge anybody to find a single image made by Apple that promoted a "generic device" while they made a device that falls in that category. And why the hell would they use a generic phone anyway? Photo stream is only available with the iPhone, not all smartphones.
If the graphics artist just had to use a placeholder, he would have used an iPhone 4 icon, he wouldn't have made a polished temporary icon from scratch that represent a device that doesn't exist. That would be a waste of time and not something Apple would encourage.
This is the real deal folks.