Overall, one can agree that Apple successfully released a deeply recoded OS without changing massively the interface. If it is true for most components of the system, QuickTime X still appear as incomplete, no finished or optimized. A clear example is the Snow Leopard installer offering you to use QuickTime 7 by default. This is also true for all users with the limited functions available on QT X menu. But for developers QT X is even more an issue and does not deliver what was expected as reported by Christophe Ducommun on his Blog (in French):
QuickTime X was very promising, but unfortunately one can not use it with the new deciding layer of MovieGate, The reason is rather simple: to use QT X you need to use the QTkit framework, and only reading operations are allowed (n edition possible). The video decoding layer of MovieGate use Core Video in order to get the best performance, but Core Video is part of QuickTime framework. So, it is impossible one can not benefit from QT X and get access tp the H.264 GPU-accelerated codecs. For working on 64-bits addressing, it is still impossible to compile the decoding layer of MovieGate, as QuickTime is not (and will probably never be) available in 64-bits. If you want to compile an application in 64-bits with QuickTime, you have to use the framework QTkit, which remains incomplete/not finished and does not offer the key functions required for a video decoding application such as MovieGate.
Other developers might be able to implement QTkit for their usage, however, only few functions are available, and QuickTime X can not really pretend to be the complete and entire replacement of QuickTime 7.
To demonstrate the current limits of QT X, Christophe ran new series of tests with Leopard and Snow Leopard:
As you can see, re-encoding a Sorenson Video is greatly accelerated with Snow Leopard thanks to the power of the graphic card. However, encoding into H.264 with SL only brings marginal improvement because one can use the hardware-accelerated coded, so only the CPU is working.
So, if QuickTime X looks still interesting on paper, there are a lot of work to be still done to really unchained its potential. The engineer team working on QT X must have had to complete other more important works to get SL ready, so we should not be surprised if Apple offers QuickTime X updates in coming weeks.
