Hmm, got mixed feelings about this. I've been planning on upgrading my normal 3DS to an XL anyway, so I have little to lose personally, but I do see why people are upset.
I suppose it depends on how the console is marketed and how extensive its exclusive library is. If it's mostly Wii and Gamecube ports, I see it more as a 'reward' for upgrading than a punishment to owners of the original 3ds, since those games are available elsewhere. They definitely have to make it clear that games like Xenoblade aren't playable on a normal 3ds, though, and maintain support for the normal 3ds so that people who own the 'old' 3ds don't feel like they've been forced to upgrade to a better version of the same thing.
I also wonder whether they're going to treat this as a new console, or sort of a transitional console. I wouldn't be surprised if this exists to buffer the '3ds's lifespan in order to align the next 'real' new handheld release with the Wii U's successor, since the implication is that they're going to have architecture that is in some way compatible.











