OS X Safari tabs were added to the iPad version of Safari in iOS 5.
Most of the rest of the features that people are listing don't seem right, like both iOS and OS X have a search called Spotlight but they aren't very similar in UI.
The ports of iWork and GarageBand felt like that to me. iOS changing from a web-driven OS into something that can be much better compared to a desktop machine.
It seems to me that contrary to Gruber's claim, OSX is moving towards iOS and iOS is moving towards its competition.