Re: I'll go with that.
Not sure what sort of "usability nightmare" is being referred to. Having trouble getting used to swiping up instead of hitting the home button, or looking at your phone to unlock it instead of placing your finger on the home button? I thought it would take some getting used to, but after a couple days both became second nature.
Since everything else works pretty much the same with the X as it did on previous models I'm not sure what else it could be...