Thanks for the confirmation on Clutter deprecation.

I've looked at QGraphicsView - it all looks good and makes sense - especially when you look at it from one application's usage - but what I'm struggling with is how the overall 'system' scenegraph will be managed in maemo 6 - i.e. Homescreen/Launcher, Video players, games, java, webkit (itself with DOM with embedded video objects etc) as well as multiple running applications + transitions/animation frameworks...

Is everything rendered in/from QGraphicsView? (and composited using alpha rendered widgets?)

Obviously I know its possible - some good examples of video integration from last year - videos-get-pimped as well as lots of other graphical goodies in the labs.

However - a single QT-based system scenegraph AFAIK hasn't been used before? Even on Mac and Windows there is an underlying windowing system which Qt renders surfaces/pixmaps to. [though there is QWS on Qt/Embedded - which provides simple windowing services?]
You still have X11 compositing with Maemo 6 around right? But you wouldn't be using it right?

With Maemo 6, with Qt, on hardware accelerated platforms, there is going to be a massive dependency on the quality and interaction between rendering backends and EGL, OpenGL ES drivers, Gstreamer/OpenMAX IL implementations etc - and then you get it all together in a QGraphicsView scenegraph - maybe with animations too and hope its all works and is performant....

or have I got things totally wrong and its all much simpler than that?

I'm coming from a hardware adaption implementation direction - I want everything to take advantage of underlying hardware - be performant in both processing power, bandwidth and memory usage.

...and I'm interested in modelling the system performance for real world UIs with particular applications running too

Thanks