Of course, it is not new technology, but we should remember that patents can take an eternity to make their way through the patent approval process. Nvidia originally filed the patent application in November 2007. For those who keep track, this was about the time when Nvidia was releasing GeForce 8800 series GPUs based on the G92 core.
The patent explains that switching between an IGPU (integrated GPU) and a DGPU (discrete GPU) could deliver greater graphics performance when needed, but save power in general applications: "While in the hybrid graphics mode, the DGPU performs the graphics processing, and the graphics driver transmits the rendered images from the DGPU to the IGPU local memory and, then, to the IGPU DAC. This image transmission allows applications to fully exploit the processing capabilities of the DGPU, while using the display device connected to the IGPU."
The first graphics chip that supported this technology were launched on September 11, 2008 and arrived as the GeForce 9M series GPUs.