http://www.anandtech.com/show/4252/nvidia-adds-driver-update-notifications-with-release-270-drivers
Unlike the Optimus service – which is a full auto update service – NVIDIA’s GeForce driver update service will be a notification service; driver updates are just a wee bit bigger and are more likely to go wrong than a simple profile update. As with the AMD’s notification service this is going to be enabled by default, as users most likely to encounter problems with out of date drivers are the most likely to pass over the option to enable driver update notifications. Meanwhile for power users the service will also have an option to poll for beta drivers as frequently as once an hour for the truly cutting edge. Notably, NVIDIA is going to be directing users to their download page rather than directly downloading the newest drivers, as they want users to be able to read the release notes first.