I'm looking forward to the stories of people actually filling these things, and then losing/corrupting them. I think that is waaaaay too large for the size/speed of SD.
When used as a generic storage with a complex write/delete/overwrite pattern, most card would start corrupting data fairly quickly.
To say that every consumer is going to use it only as a temporary medium, I think is overly optimistic.
This card probably isn't targeting the consumer market. I think smartphone cameras have cannibalized much of the Point-and-Shoot camera and PVR market. That being said, I think most consumers purchase one SD card when they buy their camera and it's the only card that camera ever sees.
- Cheap cards would start corrupting right in the middle of first "apt-get update && apt-get upgrade";
- SanDisk Extreme Pro 16GB fared much better, but still we had several failures after half-a-year;
- Failure mode in both cases - corruption in superblocks and inodes, journal doesn't help much when recovering (we use ext4).
As a result, we settled on splitting each card into two root partitions - active and standby. To upgrade, overwrite standby one with dd, switch active/standby by editing /boot/cmdline.txt, and reboot.
People unplug those things without shutting them down correctly.... quite possibly that was the problem, nothing inherent to FLASH or SD cards.
So to answer your question, space wasn't a premium, and because of the technical and human limitations of SDHC vs SDXC. I'm sure some of those cameras had firmware updates that would add SDXC support, but we didn't need it.
If it dies, I lose no data since it's just a copy of my music library. And the speed doesn't matter since I only need to sync things once and from there it's just incremental additions.
The reason I consider this is that there don't seem to be any decent music players with large capacity, as everyone moved their music playing to their phones.
I think RAM will be less of an issue for me since I run Rockbox[0] on the iPod. No need to keep the whole database in memory there. I like everything about the iPod except the software (pretty much the same as other apple products :)
Typically I just have it set as mirrored since I only shoot occasionally as a hobbyist and a corrupted card is the most likely "fail state" I'd encounter.