The panelists at the RSA session Responding to the ignored threat Macs in the Enterprise seemed to face the same kind of problems I do. Each of the enterprises has the usual defined security policies and on a daily basis they weigh the risks associated with grey areas against the productivity of their users. A na..ve user is more likely to fall victim to attacks like phishing. The ease of use built into all modern computers, and especially Macs, have made users less knowledgeable and this is a bad thing for security.
Source: https://threatpost.com/rsa-panel-review-macs-enterprise-042209/72578/