Improved created_by
The Entry construct allows any model that extends Entry to act as a Stream.

For example Profile extends Entry with the stream_slug and stream_namespace properties set.
The Profile model will now automatically be formatted by field types and will inherit all the OOP goodness.
It also can be called as a relation attribute of user like $user->profile and will return formatted.
Progress with the new stuff for user plugin. The Entry model will reduce the amount of code we have to write for this things.