This whole "learn it" credo has its limit. There were programs that turned the Windows desktop into something like 3D shooter and other weird stuff:
Of course you could learn to navigate this one too.. the question is, what is the benefit? The start menu had obvious benefits - all programs and settings reachable through one button, the GUI concept itself had obvious benefits as well. Yet no one, and I mean NO ONE was able to tell me what the heck the benefit of the start screen is for desktop and laptop users or why the Metro apps are this castrated, yet MS forces you to use them (the default image viewer is an awkward Metro app in W8.. even in desktop mode!). The explanations only come to "newer mobile devices have something like that, so.. eh.. and you will get used to it!".. And that's pretty much it.
That's not a compelling argument to warrant such a hassle.
Oh, I think I am on the verge to write another monster post, that's why I will just post this insightful comment from riagenic.com instead:
The fact that their is a "mixed response" to the windows 8 UI is the real problem. This is like coca cola changing the recipe of coke and half their existing customers complaining why change it? And coke screaming back at them saying its for your won good!
You don't radically change flagship products used by 90% of the world. You gradually introduce change if you need to. Any user friction is a fail at this level. You shouldn't see this level of friction with any established product and brand. Mercedes wouldn't do it, BMW wouldn't do it, why are MS doing it?
UI is subjective and learnt, based on history I.e. people get used to things if they have to and that becomes the natural order of things in their eyes. For that reason no UI change is technically good or bad, just different. So to hard to read Neilsen's studies in a scientific manner.
But Neilsen's isn't pretending to come from a blank objective point of view. He is attacking w8 UI based on the history that Windows has and what users know of the product. That's the no.1 problem when designing an update to anything. How do you build on the existing UI history and make something family but better. You want your users to just turn the key and drive the new car not spend 20 minutes looking for where you out the gear stick!
Ultimately MS have taken liberties because they think they have a captive audience. Just like they did with Office and the Ribbon UI. If your audience can't move from your product you start giving them not what "they" want or what they "ask" for. You start giving them what "you" want instead. MS haven't listened to users the whole year since the preview came out. And yet they expect people to love what they have made?
Sadly, Unlike with Office MS do not have a fully "captive" audience. Many are escaping to the other computing products like iPads, macs and android devices. I think Ms has overplayed it's hand this time
I agree with the "Don't write off human beings ability to learn..." Etc.. But I think we only do this if there is no other alternative to get to what we want. We are naturally predisposed to doing the "easiest" thing. In fact man has spent the whole of its time on earth trying to make things easier, that's probably what distinguishes us most from animals.
However, to change for change sake is in my view a usability fail. You can get away with it if you are the only choice in town but if there are others it's usability suicide.
Micorsoft have yet to explain WHY these changes are better for traditional desktop users. That's part of the Sinofsky "silence" issues. It feels dictatorial and doesn't give the impression that MS are in partnership with its users (or even their OEM's for that matter!). It's just very one sided affair driven by Microsofts need to get into the mobile game at all costs. Very cynical, and obvious.
It's easy to explain to users why a touch keyboard is better than a real keyboard in lots of ways. It frees up screen estate, it allows for configurable controls, it make the device lighter etc... But why can't MS explain to me why I can only run 1 app on a 27 inch monitor in Metro? Or why is it better to move me from my desktop layout into Metro when all I want to do is search for an App? they don't want to do that. they don't want to explain anything really.
Which is why they are getting all the flack now. They are the defacto standard in desktop computing so everything they do has to be held up to a higher standard than even Apple or Google. Multi billion dollar businesses are run off this windows thing, it's a big deal! Things that seem small to us techies are BIG things in the real world because of how much impact hey have being that windows IS desktop software, period.
So you have to look at Nielsens damnation in that context. It seems like lots of unnecessary pain and very little gain for desktop users. I think a lot is expected from MS and rightly so. They are the top dog (and the only dog for many).