The service section of CRM 2011 is not something I have done much with. I have had a few customers who want to use the call logging facilities but I have not seen anyone use the scheduling. So it was with interest I saw the video below which explained the fucntionality quite well.
I get the feeling that the functionality is ok but for people to use it they would probably need to customize it.
The videos are by the company PythagorasCRM.