In an effort to make the user profile easy to edit from the admin UI, the profile properties are now driven by a content.
So if you need to add a new profile property field, let's say "Favorite Sport" you can use the full power of the form builder to do so. Your field can be a drop down list, check box list or simple text field.
The same approach has also been taken for roles, allowing you to create role properties on the fly without any coding.
Any changes that you make in the UI are saved to a json file, making it easy to source control and share with team members.