Sadly, no major miniaturization breakthroughs since. And those CSACs still eat up a lot of power (as do good OCXOs), making them rough for battery powered wearables.
Surely a good opportunity to tout your recent wristware Jeff? :D
MEMS! You should get in touch with the folks at SiTime.
CSACs are small and efficient enough to put in a 1U box and that is all that is required by the markets that the manufacturers are chasing.