Jeff, one more question concerning TCC, now that I have gotten the AprilCTP workaround implemented and functioning properly within my test application (to do normal page to page transitions). I noticed it works perfectly in portrait orientation. However, when I switch the emulator to landscape and navigate to a different page, the current page is very briefly flashed onto the screen in portrait mode and then the correct animation takes place. This behavior is also noticeable in the demo you posted (to reproduce, note that I had to add landscape support to the Favorites.xaml page).
My guess is this is an artifact of how the TCC actually creates the Page transitions. As it was designed for desktop Silverlight implementations, it did not have to worry about portrait vs. landscape. Of course it could just be an emulator screen buffer issue. Do you have any further thoughts on this? I would feel very hesitant shipping an app if the emulator is a true reflection of how an application with TCC would appear on a device. Thanks!