I did not have any problems with how different the Mac App Store UI is and how it's inconsistent with the other Apple programs. Same thing for the Twitter app. It looks different, yes. But none of the points in the article made it more difficult for me to use.
Good to see I'm not the only one who thinks this. The App Store app seems like it was hurriedly cobbled together by programmers using dev art with no input or direction from a designer. It violates Apple's own HIG in so many seemingly arbitrary ways. There is a severe lack of polish. Feels very amateur. So much so that I feel like I just downloaded something off of GitHub.
How did we get another random blog entry about OS X design voted to the top? What is wrong with HN today?
How about the failure of a blog's UI that rescales a 1046 pixel-width screenshot into 480 pixels wide, without adjusting the height?