Over at the Antimalware Engine Notifications they announced an update to the antimalware engine that powers Microsoft Security Essentials, Forefront Client Security and Forefront Endpoint Security.
The update is expected in the middle of next week and the version is expected to be in the range of 1.1.660X.0.
To ensure you get the engine update as soon as it is available be sure to open your version of the software and select Check for software updates which is located at the bottom of the Help Menu.
