I have published an InfoQ news post about the AWS team's efforts to simplify centralized compliance auditing of AWS resources across multiple accounts:
Amazon Web Services (AWS) recently added the capability to aggregate compliance data produced by AWS Config rules across multiple accounts and/or regions to enable centralized auditing and governance of AWS resources. A new aggregated dashboard view displays non-compliant rules across the organization. Users can then drill down to view details about resources that are violating any rules.
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Continue reading the full post in AWS Config Gains Cross-Account, Cross-Region Data Aggregation.