It's all very well having controls for play/pause, skip and previous but, after play/pause, volume controls are probably the next most important to me. I miss the days when all phones had a D-Pad. This offered all the media functions in one simple control. I'd have preferred them to miss out the "previous" button (when does anyone ever use it?) and add a fourth giving; Play/Pause, Next, Vol+, Vol-.
It does look like a really nice device, though and it is good to see someone doing something a bit "radical" and adding buttons to a device. There are many reasons to dislike the iPhone but, for me, the main one is it's kicking off the fashion for getting rid of buttons from touch-screen phones. We don't all want to stand in the middle of the street, looking a complete pillock, swishing, swiping and pinching just to do something we used to be able to manage with the click of a button.