Ok.. what can we understand in this video?
For now all we have seen are advanced features/widgets for a very specific use, except skyline for game development. Can be good, but for rare projects and users.

I hope that the biggest features was not shown yet.
Sorry to be always negative, but when I see the amount of great new features in the minors versions of Pixologic ZBrush (release 2b). I ask myself questions.

Meanwhile on Blender they have Game Engine, Compositing, a powerful node system, UV System, GPU rendering in realtime in the Viewport, realtime shaders and move, rotate and scale modifications. In the future modeling into the render view and the upcoming Bmesh system (allow split like "split polygon tool" of Maya).
And the Cycle render engine is young and growing very fast. Most younger than iRay but already with a good integration on Linux, CUDA, OpenCL. Not bad for a free software and tiny (size).

http://www.youtube.com/watch?v=8bDaRXvXG0E

It has been over 3 years than Nvidia/Autodesk promise to integrated iRay into all Autodesk Products.

Many users of Maya and 3ds max use this softwares specially for rendering engines : Mental Ray, VRay, etc.

Maya 2013 must reach the same level or be better for realtime rendering technology. Must be faster than Cycle, stable (developped by Nvidia so can be good), shader compatibility and database, animation support, AMD's GPUs support (?), etc.

Some features are just aberrations for a big software like Maya. Some simulations are not even yet fully multithreaded because some features still running under Dynamotion. Whereas at the moment everything become real time by GPGPU compute.