http://www.youtube.com/watch?v=ZPZ7y1EDKvk
(Video on how the Micro Arc Oxidation Process works)
I find this design impressive, one case aluminum body altered by a oxidation process ( used in Satellites) to make it 5x stronger than regular aluminium and 3x stronger than stainless steel. Coupled with Gorilla Glass 2 on the front, this has to be one of the most durable handsets out there. HTC is definitely setting the standards for durability and aesthetics of smartphones.
iPhone - Sleek Sexy Back but one drop and your heart stops
Samsung Galaxy S2 - Plastic back, decent but nothing special
HTC One S -Unibody casing with military grade protection - Wow
This one definitely is going to be my successor to my Nokia phone!
/thoughts