Well, although the X100s is the best auto-ISO implementation I've seen from Fuji yet, I really hope future models catch up with where the industry seems to be going for higher end cameras. Both the RX1 and Coolpix A allow for use of auto ISO and the exposure comp control in manual mode (although I wonder if the Nikon really means to - there's a weird quirk where the conventional way of accessing the exposure comp does NOT work in manual mode, but if you assign exposure comp to a different fn button it does....). And the Coolpix A also allows you to select a minimum shutter speed from 1 second to 1/1000 in aperture priority mode. The RX1 doesn't but with useable ISOs up to 12800, its so easy to just use manual mode when you want that level of control... I'd say the Coolpix A is the best implementation I've used, with the RRX1 not far behind. As much improved as the X100s is over earlier Fuji models, it felt really limited after using those two cameras. I hope the updated X-Pro allows both higher minimum shutter speeds than 1/125 and also allows use of the exposure comp dial while in manual mode using auto-ISO. It seems to be the way to go with sensors that have such amazing ISO ranges these days...
-Ray