First, modern CDN's can use anycast (example bitgravity) to control in detail which content server a given user connects too. Second, a CDN operator can anycast it's authority servers to minimize time spent in recursive dns lookups (I believe akamai uses a combination similar to this).
Alternately, a 3rd party dns operator can use anycast to control which resolver a given user uses, ensuring that the resolver is close to the user on the internet. Since google's nameservers are associated with hostnames of the form any-in-XXXX.1e100.net I'd assume they're anycast already or will be in the future.
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Anycast mitigates this several ways.
First, modern CDN's can use anycast (example bitgravity) to control in detail which content server a given user connects too. Second, a CDN operator can anycast it's authority servers to minimize time spent in recursive dns lookups (I believe akamai uses a combination similar to this).
Alternately, a 3rd party dns operator can use anycast to control which resolver a given user uses, ensuring that the resolver is close to the user on the internet. Since google's nameservers are associated with hostnames of the form any-in-XXXX.1e100.net I'd assume they're anycast already or will be in the future.