I would definitely get the X100s if I was in your shoes.
But then again, I wouldn't have purchased an OMD.
I've owned and x100 and now a happy OM-D owner. Im sure the x100s will be the camera we all wanted the x100 to be, however the option to have a good variety of lenses for the OM-D will keep me with this system for a while. They are 2 different beasts and I don't think you can go wrong with either.
I had always planned to purchase an X Pro 1 but the non impressive AF steered me towards the OMD. I'm pretty well invested in the OMD but I think eventually I'll migrate over to an X100s and X Pro 1 (successor) combo. - I guess I just answered my own question.