It confirms what we already know - the iPhone 6s is packing a smaller 1715 mAh battery than its predecessor’s 1810 mAh. And that’s due to keeping the phone nice and slim while accommodating the components that power 3D Touch - the new Taptic engine (that sliver of silver beneath the battery) and display. The latter has also grown a little in terms of weight and width because of the extra capacitive sensors that 3D Touch requires.
It’s good to know that Apple still abides by Steve Jobs’ philosophy that everything should be as beautiful on the inside as they are on the outside; the Rose Gold iPhone’s inner screws are coloured the same shade. How’s that for finesse?
And should you accidentally smash your new iPhone 6s in your unboxing excitement, it’s been graded 7/10 for reparability so there's still light at the end of the iPhone-less tunnel.