Niles Community Schools uses it. Going on four years now. We've branded our installation "VikingNet" - consistent look and feel across three installations (sixth grade center, middle school, and high school- http://www.nilesschools.org/vikingnet).
Lapeer Community Schools will be using Moodle this year. We are connecting through the Lapeer ISD. A handful of teachers used Moodle last year. This year we will be getting training and hopefully, many of our teachers will begin using Moodle for their classes.