It will make editing software obsolete if there is no option, so its nice for those who keep the latest editing software, but for those on a budget and still using older software versions, it would not be welcome. I don't care if its added as a option, I just would not use it, space on my hard drives is not a issue.
If it needs more computational resources to be generated, it could slow down cameras with a processor less powerful than DIGIC 8, especially for larger files. So beware about "better everything".
We may need to find info on how long it takes to compress and save the file to this format in-camera. It may have merit if the time is shorter than the current CR2, i.e. shorter processing time (and obviously smaller file size).