Microsoft Live Labs has released a toolkit for developing multi-tier applications targeted to Web browsers or to the CLR (Common Language Runtime). One stated goal is to ease the process of creating software as a service applications.
As the Volta development team put it in its blog entry called Announcing Volta, "In effect, Volta extends the .NET platform to further enable the development of software + services applications, using existing and familiar tools and techniques."
MSDN, meanwhile, has launched a Volta forum.
The release has some speculating that Microsoft aims to take on Java -- more specifically, the Google Web Toolkit and its so-called "cloud programming" model for Java.
NewsFactor Network's story Is Microsoft's New Volta a Java Killer? offers a bit of insight into Microsoft's potential to challenge Sun.
Meanwhile, Mary Jo Foley has posted on her All About Microsoft blog some thoughts from Erik Meijer comparing Volta to the GWT. The biggest differences, not surprisingly, are centered arounf programming languages and availability -- the GWT has been out for about a year.