I just don't see the problem. They've changed the name of a few apps, and altered the GUI a tad bit. Notification Center obviously came from iOS, but is that such a bad thing?

What could you do on OS X yesterday that you can't do today? I'm speaking of course of the iOS similarities.

As to the question of Gatekeeper and Sandboxing: those have little to do with iOS, other than the iOS App Store has proven that people prefer simple, secure, and less crash-prone apps to a wide-open app fest we've had in the past. And they aren't even really getting rid of that, just not making it the default - and only applying Sandboxing rules to apps sold on the Mac App Store.
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