What's fresh in Windows Vista is the inclusion of anti-spyware protection that forms a new tab in the Security Center called Malware protection. Tracing the roots of this new functionality, it all began when Microsoft bought over the popular anti-spyware company, GIANT, and repackaged their application as Microsoft AntiSpyware. This was offered as a beta add-on to Windows XP in 2005. The second beta version was significantly revamped over time, and debuted in 2006 as the Windows Defender; still a beta though. By the end of the year however, Windows Defender was officially released and became an essential free download for Windows XP users under the Genuine Microsoft Software scheme.
Now in Windows Vista, Windows Defender is integrated into the new Security Center and plays a crucial role of protecting your system. Using its real-time scanners, its core job is to sniff out spyware from emails and websites, and prevents unauthorized installation of 'mining' utilities/software that slow down your system which can cause harm to your system or other systems. Like typical anti-virus applications, Windows Defender requires weekly updates so that you will have the latest protection against new spyware. Windows Defender in Vista also goes a step further to block all startup items requiring administrator privileges (basically those which aren't Vista compatible), thereby further making it tougher for any rogue programs to wreak havoc upon your system.
Under the Malware protection tab, you can also access your anti-virus settings. Through the partners' collaboration program, Vista will advise you if the virus list from the installed anti-virus application (Windows Live OneCare or Trend Micro's PC-cillin, etc.) in your computer is up-to-date.