There&s no doubt that Sony is introducing new Alpha cameras today. The only question is: Which Sony Alphas? The most reliable rumour at the moment is probably from the Nokoshita camera blog, according to which Sony is currently editing pages for "ILCE-7RM4". This brings the idea of a Sony Alpha 7R IV within reach.
A brief reminder of the Sony Alpha 7R IV: Sony presented the current Sony A7R III at the end of October 2017 and equipped it with the same sensor resolution of the predecessor Sony Alpha 7R II (42.2 MP). Since the full-frame competition has meanwhile passed in the form of Nikon Z7, Panasonic S1R (45, or 47MP), a jump in resolution to 50-60MP (or higher) would make sense for an upcoming Sony A7R IV. One should keep in mind that the Sony "R" line in the Alpha full-frame portfolio is mainly about high resolution.
To what extent a Sony Alpha 7R IV with an even higher pixel count will also be interesting for video applications depends on the readout options of the sensor as well as the available codecs and external recording options. Should Sony claim a stronger relevance for the upcoming A7R IV also in the video environment, one should hardly miss a 10 bit recording option (- even if it is only external with a 4K 1:1 pixel readout).
On the other hand, we see internal 10 bit recording with a more video-centered Sony Alpha 7S III in the current market environment (Panasonic S1 with internal 10 bit V-Log recording and Nikon Z6 with external ProRes Raw recording) as being virtually set. Whether or not the Sony A7S III will be presented today is anything but certain - the IBC in autumn is at least as good if not even more suitable.
In this context we are more likely to think of more APS-C cameras from Sony - an Alpha 7000 at the upper end of the APS-C segment would make a lot of sense in our eyes ...
But be that as it may - we won&t have to wait long - because in exactly 1 hour and 42 minutes the Sony show event starts - and soon we&ll all be smarter ...