Well, this format should help with double page spreads and I think that little by little we are all heading towards a more panoramic view of the world, most screens are now becoming wide, the Internet is therefore seen on wider shaped windows, then there is the video related work, also wide. I do like the wide format, it gives images a different and sometimes more important dimension, though like everything, it could be a fad that will last a few years.
In the meantime, why not capitalise on it.
I am interested, and would consider buying one, so long as other things have been sorted out, like fast and sharp live view, not too noisy high ISO, fast tethering, etc, etc. Chip size is no longer as important as it used to be.
I like the idea of the internal rotation of the chip a lot!.
To me, the ideal chip would be 6x7 on a camera like the RZ but with full front and rear movements.