Microsoft is developing a new tool called Windows Defender to protect users against malware. Here's some information about it:
We got the final name for the cool technology our team has been developing for Windows. The name, after long consideration by our product marketing and branding folks, is "Windows Defender"! What's really cool about this name is that it’s more positive than "Windows AntiSpyware". Windows Defender is about what Windows will do for customers, defending them from spyware and other unwanted software. Our solution has really been about more than just the standard definition of "spyware". We’ve always said we will provide visibility and control, as well as protection, detection and removal from other potentially unwanted software, including rootkits, keystroke loggers and more.