UAC adds additional security in the underlying kernel components that trigger UAC alerts. Since disabling UAC disables these additional kernel security features, it is useful (from a security standpoint) to leave UAC enabled. The issue is that the UAC prompts are annoying, and most users end up disabling UAC when they get sick of seeing these prompts.
The User Account Control tool (beta) form Norton lab has been designed to replace the Vista UAC, to simultaneously make your system more secure while significantly improving user-friendliness.
Norton Labs is working to create a white list of unnecessary UAC prompts so that users can benefit from the additional kernel security features while only are required to interact with a UAC prompt on rare occasion.
The net effect is that many users find the UAC security clearance and prompting process annoying, especially those who are a computer’s only user and have all the latest security software installed and updated. More details and download (1.25Mb)