I see it in Windows Task Scheduler:
It checks for and downloads updated game and application profiles (including SLI profiles) from Nvidia's server.
It's not too useful if you regularly update the Nvidia drivers since the latest driver version includes the latest profiles.
NVIDIA Update keeps your PC up-to-date with the latest NVIDIA drivers by notifying you when a new driver is available and directing you to the driver on www.nvidia.com.
Starting with R275 drivers, NVIDIA Update also provides automatic updates for game and program profiles, including SLI profiles.