This past week I was delivering some events for customers on supporting Mission Critical databases with SQL Server 2008. During the compliance conversation I mentioned that there were a couple of new resources available related specifically to PCI compliance.
Parente Randolph published a whitepaper on how to leverage SQL Server 2008 features to meet PCI compliance.
Furthermore, these auditors presented a TechNet webcast on the same subject.
I would also highly recommend the SQL Server 2008 Compliance Guide which will complement the above resources with technical implementation examples.