Let's see..
- The Address Book and Calendar makeovers. Nobody liked these.
Ah, true, I've been on 10.9 too long to remember those
Yes, I much prefer the Mavericks Calendar
- Expose and Spaces dumped for Mission Control, to much chagrin.
Well, its personal preference. I much prefer the Mission Control.
- Launchpad. Lion crammed it down the user's throat while Mountain Lion sabotaged apps that allowed the user to edit it.
Nobody crammed nothing none's throat. Its pretty much an optional UI feature fr people who want to have a more visual way to launch their software.
- Mac App Store. Whether this is a change for the better or worse is very debatable (I'm leaning toward better, actually) but it's obviously iOS related
Sure, the historic reason might be with iOS and other smartphone software marketplaces, but this is the direction the industry has been heading to for quite some time. Windows and Linux also have it. Actually, Unixes have had software repositories for quite some time now. And Steam, a prime example of software management platform/marketplace was launched years before OS X App Store.
My only gripe with the App Store is that it requires you to create an Apple ID, even for free software.
- The new way to change spaces with the trackpad is iOS-inspired. I'm not a fan... it feels slow.
Then use the old keyboard way.
- The disappearing scrolling bars caused a big stink back then though I always thought they were a good idea.
Dissapearing scrolling bars are a very nice design IMO which gives more space for meaningful content. As to big stink... well, people are naturally resistant to changes.
- Reverse scrolling is a big mess. Sucks that I have to use Scroll Reverser for mice scrolling to feel coherent across desktop operating systems.
It took me few minutes to get used to scrolling. And btw, there is a switch in system preferences.
- The linen backdrop. Gotta say I kinda like it actually in both OS X and iOS even if I grew tired of it. Lots of people hate it though.
I liked it too TBH. Didn't know it was iOS inspired though.
The integration of FaceBook, Twitter and all the other crap.
Tons of people use platform like Twitter, Facebook, Google, Wikipedia and OS which makes them more convenient to use is a welcome thing in my book. I find it very convenient that I get notifications that somebody is messaging me on FB in my notifications. OS X was always about usability/functionality, seamless integration with most popular internet platforms is thus not a metamorphosis but a logical course of action. Again, if you don't like those services, then don't use them. Nobody is pushing them on you.
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How about iBooks in 10.9 having a more flat icon?
I like the new desktop icons a lot (iBooks, App Store, iTunes) and I hope that the rest of apps will follow the style. Its much cleaner then the old ones. And it doesn't look silly at all, as opposed to the majority iOS7 icons.