According to Apple and Google, this is no biggie. Although iOS 6 will not have YouTube pre-installed - unlike the versions before it from the original iPhone onwards, back when Google sat on The Board - however it will still work through Apple's browser, Safari. Google, meanwhile, is building its own, new YouTube app that will become available through Apple's app store.
The Wall Street Journal is reporting the story as the emergence of an even wider gulf between the 'erstwhile partners' but we will have to wait and see where Google's new app development takes us.
It would not be a tremendous surprise if, considering some of the accusations flung at Google by the EC and others, YouTube became beautiful on Android and functional but basic on iOS. This is pure speculation. The fact is, we will have to wait and see if there is anything in this that resembles handbags at dawn, especially with Google's Nexus 7 now on the market.
Google said in a statement that it is "working with Apple to ensure we have the best possible YouTube experience for iOS users", but it did not say exactly what that entails.