Recently, Microsoft released the first Beta version of Windows Vista (formerly codenamed "Longhorn") which is set to be released at the end of 2006 as the new flagship operating system from Microsoft. One of the new components being introduced in Windows Vista, as well as being used in other products, such as the upcoming new release of Exchange Server (due second half of 2006), is a new scripting language dubbed Monad. Researchers have already uncovered a potential vulnerability in Monad that could be used to spark a virus or worm outbreak. For more about the Monad flaw, read this News.com article:
First potential virus risk for Windows Vista found.
Update: One day after the news of the vulnerability in the Monad shell component, Microsoft announced that Monad will not be included with the initial release of Windows Vista. For more details, check out this article from Network World: No Monad scripting in first Windows Vista