Only difference is size. If people have a use for a big tablet like this, they'll buy it. And it'll do well, and if not, it won't.
I considered whether one would be useful for me or not but I just don't know. I have a Mini at the moment, and I like its portability though most of the time it is stationary. I regularly use it for study and wouldn't mind having two browsers open side by side or a browser and notes app open at the same time. Could do that with an Air 2 as well but the bigger size will probably be better.