It could be possible in a certain way but the game would have to be created in order to offer 60fps to those playing online and locked 30-45 fps for those not connected.
How I think it would be possible is simple. The reason you don't have 60fps in most games is because the games are jam packed will all kinds of effects, lighting, AI, physics, assets etc. Take a game that has less of these things and it would be possible to run at 60fps.
So How I would do it is let the cloud handle some of the effects that do not require a player input. Animation in the background, lighting, DOF, soma AI, some physics etc. Then because the console cpu doesn't have to handle all these things at the same time it has the extra ressources to render the game at 60fps. This is what I understood when they first talked about the capabilities of the cloud. If I'm totaly wrong feel free to let me know.
