New features in the beta of Microsoft Security Essentials include:
Windows Firewall integration - During setup, Microsoft Security Essentials will now ask if you would like to turn the Windows Firewall on or off.
Enhanced protection for web-based threats - Microsoft Security Essentials now integrates with Internet Explorer to provide protection against web-based threats.
New protection engine - The updated anti-malware engine offers enhanced detection and cleanup capabilities with better performance.
Network inspection system - Protection against network-based exploits is now built in to Microsoft Security Essentials.
Please note that the network inspection system feature will not be enabled on Windows XP. This is because the network inspection system requires the Windows Filtering Platform (WFP) in order to run, and WFP is only available in Windows Vista and Windows 7. However, if you are running Windows XP, you can still use all other beta features.
To download the beta of Microsoft Security Essentials, click here to visit the Microsoft Connect page to register for the beta. Once completed, you will find the instructions for downloading and installing the beta. This is a limited beta available in English (U.S.), Israel, and Brazilian Portuguese (the beta will also be available in China in Simplified Chinese later this year) and is available to genuine Windows users on a first come, first serve basis until the allotted spots for the beta have been reached.