The idea of real-time quality graphics is what fuels a great deal of our experimentation with game engines. The idea that we can have lighting, textures, geometry all being rendered to us in real-time is what it is all about, if the quality of that render is high, then that is another step up and if we get interactivity, physics, effects and more then we are set.
The VRay guys (Chaos Group) have a new release of their renderer plugin for 3ds Max which is the standard for architectural visualisation which they have tagged RT (for real-time). I havent had a hands-on play at all as yet, but if the videos are anything to go by, we get one of our viewports continuously rendering away as we update the model, lighting, camera position etc.
I think this is a stretch to refer to this as a Real-Time release of the renderer, as the viewport is sitting there trying to keep up. My thoughts are that the last thing we would want is our computers struggling away on rendering a viewport making all the others slower. The idea is great and it is what we will take for granted in years to come. Have a look at the vids to get a feel for the state-of-play - one things for sure, VRay makes for some very pretty renders - they look awesome in the viewport.