I said it before and I got downvoted to hell, but I'll say it again. Just because those of those of us on HN can deal with these UI changes does not mean that the vast majority of the public can. We ARE the minority, and when designing systems we should expect people to be computer illiterate. I am the computer-go-to-guy whenever something goes wrong or family members/friends need help, and ANY UI change always leads to difficulty. Something as small has the UI change from IE7-8-9 was enough to trigger a "how do I use this thing?" every single time. Same when MS Office introduced the ribbon.
It's the reason Apple have done so well - they didn't invent anything new which hadn't already been done, they just added better UI that appealed to the masses.
I have to say, I agree with most of what is written in that blog, I've gotten used to some of the changes now but still a lot of the time keep looking around to see where the hell something has gone (the attach files expands out to reveal more options, why the hell is add URL link under attach options?)