Pretty much how I thought it would be. Had a hard time beating Hell when you still had the chance to level up? Only way to make it harder is to cap you before you beat Hell and throw you against the wall in Inferno!
Contrary to what I said that Inferno difficulty level would be a secret choice that would only appear after a player beats the Hell level, it seems that another requirement is that you have to level cap your character up to 60 as well.
Now, I'm even more excited for the Beta and ultimately for the games release before the Christmas holidays.