TechRadar has posted a review of the X Pro 1 with excellent data. The charts based on RAW data reveal the sensor inside of the new Fuji to be an absolute champ. Signal-to-Noise measurements put it in the same class as last-gen Full-Frame cameras like the EOS 5D Mark II. Obviously, the upcoming next-gen cameras will widen the gap again, but this is still huge.
As with many of the reviews, they punt on the autofocus issue, calling it adequate. I hate limp-dicked reviews, and while this review is otherwise fine, autofocus problems in a $1700 camera are not something that are left alone. That is bad and should be stated that way.
That said, the performance of the images is amazing. Resolving power remains the same up to ISO-6400, putting the camera squarely in FF-land. Obviously, it drops off where the FF gear does not, but the benefits of the new sensor as regards dynamic range are immense.
The autofocus issues are big, but it is apparent that getting this level of quality in this small a package is going to be interesting to serious enthusiasts. I think that pros need not apply, but for the camera-lover with some coin to spend, this Fuji should be strongly considered.