MediaTek is the first company to announce a phone chipset with an integrated 5G modem. Solutions from other vendors have, so far, centred on a separate 5G modem. The announcement was made at Computex 2019 this week.
Indeed, we weren't expecting an integrated 5G modem before, perhaps, Huawei shows off Kirin 990 in September (current situation pending) or Qualcomm's Snapdragon 865 which will probably be announced in December.
Details aren't exactly plentiful on when we might see the hardware in handsets - it doesn't even have a proper platform name yet - but as with other MediaTek products expect them to come to mid-range phones predominantly. We'd bet on early 2020 for it appearing in phones, maybe at Mobile World Congress.
The new 5G SoC (System on Chip) is based on the 7nm manufacturing process like many current high-end phone platforms and incorporates ARM's brand new Cortex-A77 CPU core design and Mali-G77 graphics. That's quite a step forward for MediaTek who hasn't always managed to use the latest and greatest designs.
The modem is all MediaTek designed though, called the M70 5G modem supporting 5G NR sub-6Ghz. It can support download speeds of 4.7 Gbps, which is shy of Qualcomm's 7Gbps specs for the X55 modem. The M70 also doesn't support mmWave 5G tech, which is rolling out in the US currently but not Europe.