Maybe I can start an 'X-S1 Confidential' thread . . . .
I bought one as a longer-armed brother to my X10: Thought it would be easier on my brain to eseentially only have to remember one set of menus for two cameras. Essentially the X-S is an X10 on steroids. I love mine for lots of reasons, but mostly this:
It's truly intoxicating to go from macros literally inside the lenshood (like the X10, it'll macro right down to the front element, although you get great macro at 135mm equivalent with the standoff distance that allows), then with a few menu prompts and a twist of the barrel, you're out to 600mm. It's magic. Flawless flash. Built like a tank. I leave the house with it, a spare battery (I've yet to use two in one day, they last a long time), the EF42 flash (forget alkalines, use Eneloops), and that's it. It won't replace a 5DMk3 or a D600, but it's a lot of fun for $599, and right now, that matters to me.
My usual MO is to use the X10 when I want to be inconspicuous and I don't need the tele reach, and the X-S1 for everything else.
An X-S2? Gee, I wish . . . . drop the X20 updates into it, where do I sign up? Of course the other thing that occurred to me: Morph this body with an XP/X100 sensor and an X-mount, and use the X lenses, voila', instant SLR without having to deal with Nikon. Who knows?