One of the reasons why QTKit sticks around is that it has been around since 10.3 and it's foundation is even older going back to I think 1992.
So I think QTKit is an edge case and probably not used by a ton of developers directly. I think the 80/20 rules also applies here... by porting 20% of the frameworks you get 80% of the functionality.
That being said: I think that if it happens it will happen over time. Deprecating something in Mavericks does not mean that it has to be gone in the release after Mavericks. GC was with us for way too long... But you can replace almost anything within lets say 5-7 years. That would be 5-7 major releases.
So I think QTKit is an edge case and probably not used by a ton of developers directly. I think the 80/20 rules also applies here... by porting 20% of the frameworks you get 80% of the functionality.
That being said: I think that if it happens it will happen over time. Deprecating something in Mavericks does not mean that it has to be gone in the release after Mavericks. GC was with us for way too long... But you can replace almost anything within lets say 5-7 years. That would be 5-7 major releases.