Is Microsoft trying to ignore the UML standard and lock customers into their own modeling language?
No. The UML standard is a weak one, and for this reason, most UML tools are unable to seamlessly interoperate. While we recognize the value of UML for documentation and for understanding software design, domain specific languages will enable you to work at higher levels of abstraction, and to focus with precision on issues relevant to specific domains. Over time, Microsoft will provide additional domain-specific modeling tools, and we will continue to work with our partners to bring UML tools to Visual Studio 2005 that are built on top of our modeling framework.