In addition to viewing the people in your projects, you can cross-reference milestones and todo items by their status as well.
Click the 'People' dropdown to show the available fields you can use.
When you select a field, all the choices for that field fill the area below. Also, all the choices are cross-referenced by users assigned to milestones and todo items and presented in pie charts.
When you click on a choice, all the milestones and todo items are filtered to match that choice.
When you click on a person, all the milestones and tasks are futher filtered such that the selected person must be assigned.
To return to an unfiltered list, click on the selected choices and people so that they are no longer selected.