The communication wizard and communication lists are great! The next layer of usability would be to provide the ability to organize segments by category. Currently, they are sorted alphanumerically.
I've created lists for large groups of people in our organization (All Volunteers, Community Group Leaders, Parents of Students, Parents of KidSpring Children, etc.), and I've added segmentation for Campus, Gender, Age range, and marital status. Organizing the segments in related groups will help our ministry leaders communicate with specific segments of groups more efficiently.
Here's the way it works now (click title above to view image):
Here's my suggestion (click title above to view image):