SophosLabs didn't believe claims that Windows 7 and its User Account Controls were any more secure than previous versions of the OS, so they tested (albeit somewhat oddly) a clean install. Result? A reminder that you should always use protection.
The way the test was conducted is that ten viruses were introduced into a clean install of Windows 7 with the UAC settings on system defaults. While only one virus was blocked, two technically did not function properly for whatever reason. Still, this doesn't leave much hope for those who decide to skip automatic patching, firewalls and anti-virus applications. Let's do the whole "Safer Computing" thing, shall we? [Sophos]