If you want to show posts from the current logged-in user, you can use the author parameter.
[loop type="post" author="this"]
If you want to show posts from a user role..hmm, that would be trickier. Is that something you’re thinking about?
User role-related posts would be useful, but I think in my case I can make-do with just user-posts (although I have to customize the php template for each user then.
In the newest plugin update, I added a way to show posts by user role.
[loop type="post" role="editor"]
To get posts by current user’s role:
[loop type="post" role="this"]