To explain a query presently we pass in a type but we receive a BsonDocument. That works, but it would be so much better to return a strongly typed object that matches the data returned from explain.

Today:
public static BsonDocument Explain<T>(this IQueryable<T> source)

Tomorrow:
public static QueryPlan Explain<T>(this IQueryable<T> source)

QueryPlan is a class that (AFAIK) is yet to be defined. I have a working version which returns a static type (which has properties you might expect like CursorType, etc).

I would like to submit this back to the driver. What GitHub branch would be best to start from and to issue a pull request back to?