VSMs are a powerful way to communicate complex process information in a simple way.
However, most of the time when I'm working on reducing in process waste, I will map the customer value chain from left to right using self adhesive notes with one actiivity written on one note. Once the sequence of events has been mapped and agreed, the mapping team will agree which of those activities add value and place these above a horizontal line. The non value adding activities are placed below that line. This is a quick, visual way to identify and remove waste, especially in processes which have a high number of manual activities.
An example of a VSM is below. The yellow bursts are Kiazen Bursts which identify how the process or workflow could be improved. I created that map using Visio 2007