I have been using the latest OS on my MacBook Air for about a week now, and in general I really like it. Not Earth shaking, but solid, and the improvements really add up to a better experience all around.
The UI – briefly
The first thing that you notice is the flat visuals. Bowing to the contemporary design trends, the windows, the visuals, and all the other decorations are devoid of shading, gradients, or any other visual eye candy. Naturally all the skeuomorphic bits are long gone. Neither good nor bad.
Of course, with it comes a new typeface for the UI, Helvetica Neue replacing the long time OS-X typeface Lucida Grande. Unlike a lot of geeks on Slashdot who wailed like they were having their hands lopped off, I don’t really mind. In fact, with such a large change of the UI, it would seem de rigueur to go all the way.
Of course, these changes alter the look and feel to better mimic the experience on iOS 8. So it is not a surprise that many of the changes are to applications that will help unify the experience.