I'm thinking it'll be at least $900 - it looks like a tank which means its probably at least as well optically corrected as the 14mm. And at f1.4, I think we're looking at a pretty pricey lens. But I read the subtext of this thread as "will it really cost that much more to just buy an X100s instead"? My gut tells me it won't cost much less than the X100s, so if you'd rather have another camera than another lens, seems like a reasonable approach.
My thoughts exactly.
You lose a stop and probably critical sharpness, but you get a camera body to go with it...