I have heard that Nintendo will be using cartridges for this system. Considering the advantages of a cartridge, I do see this as a pretty smart move on their part. I have nothing against CD based games of course, but the advantages of cartridges just outweigh those provided by discs. Namely:
-Instant load time, no waiting
-Can be modified with additional features
-Are more resistant to damage
-Last longer
-Requires less space to function
The thing that I hope they address with this console is making it easier for people to back up their data. This was a complaint that a friend of mine had about the Wii U. The way that it is now, user data is tied with the system, meaning that trying to save your data is very limiting and sometimes impossible. Like... she and her family use the same Wii U and she is not able to take just her data and get her own Wii U; she can only do a full transfer that takes everybody's info onto a new console. So someone would need to start over from scratch just for that. So that's quite a hassle.
Another example: A friend of mine bought a new Wii and he tried to load his games that were stored on the SD card onto the new system. No dice. Despite the fact that he had already paid for these games, Nintendo still wanted him to pay full price for all those games again just so he can play them on the new system. He was understandably outraged.
So yeah, I do hope that his is addressed. These issues are not that prevelant on the X-Box or Playstation. At least from what I heard and experienced (at least with Playstation). So hopefully Nintendo will address this and make it easier for people to back up their data to avoid issues like "having to pay full price for a game a second time even if you already legally own the copy".