Specifically, he promised it will be easy to turn off the 3D functionality on the new system, allowing people to play games in 2D mode. The reason for the 2D/3D toggle option is reportedly due to concerns over the health effects of viewing 3D content for extended periods, as this has been known to cause nausea, headaches, or dizziness on some people. It's unclear if developers will be tasked with optimizing their games for both modes or if the hardware will somehow be able to handle the transitions between 2D and 3D.
Iwata also mentioned that Nintendo will add new "anti-piracy measures" to limit game theft. He wouldn't discuss the details to avoid giving "hints" to hackers, but said they're concerned that people are becoming more tolerant of piracy.