I always found this somewhat inelegant. I suppose given all the constraints, its OK, but it feels like such a feature (such as the collection initializers) should be based on language constructs, not compiler special cases.
Lucian Wischik gave a really nice talk recently about language design at Microsoft and he indicated that they are trying to do it in that order from now on: determine the feature that's needed, add the necessary plumbing that would allow programmers to implement it, and implement it as a reference implementation.
