On this topic, today HP Cloud opened access to their Akamai Anycast DNS service with 75 edge locations. Pricing is about the same as Route 53 ($0.35/domain + $0.55/million queries). Not as easy to use as Route 53 yet - configuration is via API only.
I understand how DNS works. UDP packet to server, returns IP from host via UDP, and or requests DNS record from a different DNS server with more information about the domain (all the way up to the root servers).