This is a fantastic article detailing the costs of incident response and sheds a strong light on the value of early detection and remediation.  I certainly recommend this read and that every CIO/CFO/CSO save and tuck away this formula for future use.  Every tool you can bring to bear on the omnipresent internal ROI debate is worthwhile.

http://www.tenable.com/blog/the-cost-of-incident-response