Norton AntiVirus 2009 provides fast, responsive defense against all types of malicious software including viruses, spyware, worms, and other software threats. It protects your system without slowing it down. Rapid pulse updates every 5 to 15 minutes help to ensure that you're protected from the latest threats.
Working quickly and quietly in the background, Norton AntiVirus requires little memory and system resources. The new Norton Insight relies on extensive online intelligence to target only those processes at risk, resulting in faster, shorter, fewer scans. And the new Norton Protection System employs a multilayered set of security technologies that work in concert to detect, identify, and block attacks. Version 2009 improves on product performance.
Read the rest of the article here