It's interesting to that it took this long, just considering the utility of each company. If Apple disappeared tomorrow I'd be moderately inconvenienced, I'd have to pick up an Android handset instead of my iPhone and maybe set up some new podcast feeds. If Google disappeared the world would screech to a halt.
How's that? To search the web, I'd go to DuckDuckGo or Bing or whatever. Other companies also provide web mail, maps, office document solutions, etc. Google's definitely better at those things, but using a worse version of those products would not cause the world to "screech to a halt." Probably the most disruptive thing if Apple vanished would actually be every tech company suddenly needing to figure out how to use…
But if Apple disappeared I'd be screwed.