It's a mystery to everybody outside Canon (and a small number of people even there). But here's a prediction (read: wild guess):It is a mystery to me where the currently mythical R1 will land. I don't see it going below the R3, but I also don't see it setting a resolution record. It seems like 30-50 mp might be the sweet spot.
Within a year or a bit more, Canon will announce (and hopefully release) two high-end bodies:
* R1 with 45 megapixels (just enough for 8K, no more) and other specs matching or exceeding the R3.
* A 90 megapixel body, either R5s or R3s depending on which body type they see better for it; probably the latter, as it would make heat management easier.
Another prediction (much safer): the longest canonrumors discussion thread about both of those will exceed that of the R3.