I like the idea of markdown but there is just too much missing with most implementations and I think the primary use case is to move away from XML due to verbos

I like the idea of markdown but there is just too much missing with most implementations and I think the primary use case is to move away from XML due to verbosity and readability. I'd really like to see a new API to allow creators to create their own markup languages directly in the browser with native support to map the markup to the underlying renderer.