<p>Does anyone know if there is a debug visualiser for this yet along the same lines and the linq to SQL debug visualiser?</p>

There isn't one that I'm aware of at the moment (hope to be shown otherwise by other answers here), but Julie Lerman has a post
"An extension method for visualizing ObjectStateEntries"
where she walks through creating a debug tool that pops up a WinForm for inspecting the state of entities via their EntityKey.
Not quite a visualizer, but seriously handy when you need to tease apart ObjectStateEntries to debug change tracking scenarios.