Starting with Chrome 13, we’ll have HTTPS pins for most Google properties. This means that certificate chains for, say, https://www.google.com, must include a whitelisted public key. It’s a fatal error otherwise. Credit goes to my colleague, Chris Evans, for much of this. The whitelisted public keys for Google currently include Verisign, Google Internet Authority, Equifax and GeoTrust. Thus Chrome will not accept certificates for Google properties from other CAs.
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ImperialViolet - Public key pinning
This is why Chrome wasn’t effected by the recent Iranian SSL shenanigans.
