What happened to Miles?

Grant Shaud left the show after the 8th season to pursue other projects. He felt he had done it long enough and wanted to move on.

So Miles was offered a big network position in New York and that was the reason for his departure. He was mentioned occasionally and he and Corky tried the long distance marriage thing. However, a few episodes into the final season, Corky breaks down and tells Murphy they are getting a divorce.