Real numbers are starting to trickle out. LG Uplus, Korea's #3, intends to "complete all major cities" in 2019. Korea's three telcos nominally went live in December, but are only accepting a handful of business customers. They expect 5G phones from Samsung & LG in March.
The other Korean telcos, KT & SKT, have a total of 3,000 bases deployed. All three are taking steps to fill their networks. LG is funding Korean game and VR companies. SKT is working with Seoul for an advanced traffic information system.
The Koreans have only discussed mid-band 3.5 MHz frequencies. Samsung and KT were pioneers in millimetre wave and I hear rumors. But I have no confirmation.
China will deploy 170,000 5G bases in 2019, Nomura reports. (I'm factchecking.) The Chinese also choose mid-band, including over 100 MHz to China Mobile at 2.5 GHz. CM also received some 4.9 GHz spectrum, which is used for Wi-Fi in the West.