It seems to be tough to get a straight answer out of you, for you answer a question with a question. Good tactic in some ways, for it gets people to think, but not so good in others for I will just ask more questions.
Not that experienced and I don't and won't have time to experiment with other OSs until I retire. That's why the questions.
I'll assume the first screen with the browser open is the actual desktop and one arrives on the second screen somehow via a button or shortcut, which is somewhat of a full screen start menu.
If that be true, I do see the correlation with the Start Screen in that its full screen menu. Other than that there's no resemblance, for its all icons.
This leads me to another question > Can the icons be personally arranged? In columns? Columns named? I'll assume not, for for the menu has other categories which I'll guess open specific icons for that category. I'll assume all that for now, until/if I'm corrected.
If all that be true, then I think MS has a lot up on that. To me this is the beauty of the Start Screen and the new system:
1). It was a relief to see the Modern/Metro design and tiles instead of icons > Icons I looked at for years > Icons plastered on my Taskbar and desktop because I disliked going into that little Start Menu. I know I wasn't alone, for I've seen and read that a lot of others did too. What you've shown so far reminds me of that even though they're positioned symetrically. It looks like an ugly mess to me now. Once I've seen what I see as beauty, its difficult to look at ugly again.
2). It's full screen. Much easier to see.
3). Live Tiles conveying personal information to me. A combination of an icon and gadget. Performing this far quicker with less resources. Rather ingenious to me. The process and flow of what I want to perform in an order I decide is much easier and more organized.
It also reminds me to stay on top of things such as answering emails or messaging, notes, reading news, my calendar, scrolling pictures of loved ones & friends, and the like. I don't do social sites, but I would imagine it helps with those also.
At my age I still have a good memory, but its getting shorter. When I open to a desktop I have to remember all this. I have to remember to open up individual programs or look at a gadget to get that information. This is what I mean when I say that 8 is more than an OS. Its an aid to help us live in a more organized fashion. I don't know how many times just after I've shut down or put it to sleep that I forgot to do something like answer an email, message, or what have you only to go back to do it. I'm finding myself doing that less now.
A machine interface doing work for us, for that's what machines do. If one finds that amusing, then walk or ride a horse instead of driving or flying. Cut your lawn with a scythe. Wash your clothes in the river. Type your letters on a mechanical typewriter, for you can't email.
4). Arranging tiles in an organized manner as I see fit. All in columns that I can name whatever I want.
5). Using Store apps more often than using a browser > A browser where I'm more susceptible to virus and malware surfing the Net.
6). I'll get to do this across multiple devices. that all sync.
This will all get better in 8.1.