Hi,

I am requesting a slight improvement in behaviour concerning extra elements in typed class maps. Currently the driver expects the property in which extra elements are stored to be of the BsonDocument type. However, this may not always be possible or reasonable. It also requires coupling between the project containing the model classes and MongoDB.

In essence, I ask to remove this need to reference the MongoDB driver due from the model space. I think the safest way to go about this without breaking compability is to allow the extra elements container to be a IDictionary, ICollection of key-value pairs, or something along those lines.