Apparently I’m almost two weeks behind as, according to DPReview, Fujifilm announced the new TCL-X100 1.4x (50mm equivalent) teleconverter on April 16th. DPReview state that price will be announced later. However, they then post a press release, which gives a price:
“available in May 2014 in silver and black for $349.99.”
Fujifilm Japan has it on their website here, showing a release date of May 25th and an “open” price.
It shows up on the dedicated X100s page in English here and if you scroll down, you can find the 50mm teleconverter section and see a nice portrait taken with it. Clicking on the ‘For More Information’ button will take you to more specs, etc. and also a link for more sample photos (clearly, someone got a trip to Guam out of this).