Quote from miles_dryden
5 difficulties, no Easy mode.
So...what's the deal here?
If I remember correctly, that's how it's done on the consoles in terms of Monster Power level. Each difficulty is 2 monster power, so it bottles down to 5 difficulties.
Normal, Nightmare, Hell and Inferno stays as is on the consoles. So you have 2 sliders to work with; Difficulty and overall level.
Perhaps they simply showed the console version of that one screen. Who knows.