IntelliSense based snippet handling with Visual Studio 2010 SDK MEF Based text editor

Using the new Visual Studio 2010 SDK developing against the MEF based editor structure there's a question:

How can I use the MEF editor interfaces to handle snippet behavior in IntelliSense? The ICompletionSession itself is not a problem (e.g. get the available snippets) rather filling the snippet, handling the subsequently expected actions like 开发者_JAVA百科tab, enter behavior, text replacement, etc.

Is there any way to do that without a language service? Checking the built-in behavior in Visual Studio base editor implementation they built the MEF interfaces on top of a set of language service based objects.