Well, what Google does is it gets a list of revoked certs from CA's, decides which ones are "really important" and sends those to the browser. So yes, in effect, Google decides which certificates are revoked. It's all covered in the article.
No. You're not following me. You think I'm describing agl's point. I'm not. I'm saying that beyond CRLsets, certificate pins also allow Google to detect misbehaving CAs. CAs have power only to the extent that Google allows them to have power by keeping them in Chrome's root CA key store. Google can pick among most of the current CA's and put them out of business on a whim.