As you probably know, Microsoft decided to make SharePoint designer is free, and here are some nice articles on how to use SharePoint Designer and some deployment considerations.
By Mark Miller and Asif Rehmani at EndUserSharePoint
By SharePointBuzz: Recommendation for all Organizations
Remember, with great power comes great responsibility – use SharePoint Designer appropriately within your organization. Therefore, it is highly recommending for all organizations to consider Locking Down SharePoint Designer.
By SharePoint Joel: