Wow, a nice update. Mainly for the much faster lense. F/5.6 is really too slow for the older RX100 and RX100M2

The Sony RX100M3 camera will not be announced tomorrow as previously reported (this is why I generally do not like to recycle rumors from other websites, unless I know the original source). The RX100M3 will be announced in few weeks and it will have a new 24-70mm f/1.8-2.8 lens (not the previously rumored 28-100mm f/1.8-2.8 lens). Here are the rest of the RX100M3 specs:
20MP sensor (same as RX100M2 model)
ISO range: 125-25600
New 24-70mm f/1.8-2.8 lens
Built in EVF (SVGA OLED Tru-Finder 1440k dots)
Tiltable screen (180 degrees up)
Record in XAVC S format (same format of the Sony A7s but without 4K output option)
Almost same size and weight as the current RX100/M2 models
All other specs are the same of the current RX100II model.
Price is expected to be around 800-850 EUR (around $800-$850 in the USA)
via Sony a77M2 camera announcement tomorrow, RX100M3 to be announced later | Photo Rumors.