Although it looks bigger, the K-S1 is roughly the size of the Canon EOS Rebel SL1. Plus it's got a strobing light on the grip to jazz things up. (You can turn it off, of course.)
In addition to the glowing colored lights, the body will be available in "fabric" colors like cotton beige, linen brown denim blue, tweed gray as well as "night sky" options such as sunset orange, dusk gold, moon silver, dawn purple and midnight black (green and black).
The HDMI and USB connectors sit right behind the grip.
In addition to lighting up the controls, Pentax puts the mode dial on the back, where you operate it with your left thumb. The company did this so that it's more like a phone, with all the controls on a single plane. Also, look at how large that viewfinder eyecup is.
Moving the mode dial from the top to the back allows for a much narrower camera. The only controls left on top are the exposure compensation button, ajdustment dial and Pentax's hypermanual green button.
Unlike most dSLRs, the K-S1 doesn't have any connectors on the left side, just the autofocus/manual focus switch.