Tldr?

"To date, there are no cases of Omicron which are reported as having been hospitalised or died through routine reporting. As a result, it is not possible to compare the risk of hospitalisation or death with other variants. However, it should be noted that most of the cases have a specimen date that is very recent and that there is a lag between onset of infection and hospitalisation and death. Future updates will assess severe outcomes from Omicron cases against Delta cases from the same time period."

If Omicron continues to grow at the present rate, Omicron case numbers are projected to reach parity with Delta cases in mid- December (this was dated 10th Dec).

Vaccination is less effective against Omicron than against Delta. But shortly after a booster dose, there is about 70% effectiveness.

I haven't got on to anything about hospitalisation rates vs Delta yet; it may still be early days for that.