Malware on Vista rare compared with XP
Microsoft has published a study of infections by Operating System based on recent MSRT cleaning statistics. While MSRT cleans only the most major malware incidents, this study helps confirm that Vista's out-of-the-box settings and architecture clearly provide security benefits.
Malware on Vista rare compared with XP
http://blogs.pcmag.com/securitywatch/2009/04/malware_on_vista_rare_accordin.php
Microsoft Security Intelligence Report Volume 6
http://www.microsoft.com/security/portal/sir.aspx
QUOTE: Comparing the latest service packs for each version, the infection rate of Windows Vista SP1 is 60.6 percent less than that of Windows XP SP3.