Indeed. What I'm reading is, "Google Public DNS and OpenDNS are relatively centralized, meaning CDNs might deliver you content from a cluster in Great Britain rather than your home country Germany because your DNS server is located in London. Now, you will get content from Germany again." The article makes it out to be something fantastic and exclusive to these services when the news is actually that these services used to have a big problem in this regard, and now they're working to fix it.
While this is true for most consumer users who work using their providers DNS, for networks such as enterprises/corporate locations, it's common to find they all share a common internal DNS resolver, which may be located in one physical location, while the clients are sprawled all about over the world.
I think this does give a bit more power to the geo-aware dns services (such as Cisco GSS), if they implement it.. but it's a long way off, as many ISPs and networks would need to upgrade their resolvers to support this extension.
I have found setting custom DNS breaks many coffeeshop and airport wifi hotspots, and so I don't recommend it for the general user. I can't imagine there are that many people using Google's DNS or OpenDNS.
You could change the DNS settings on your home router, so when your machines pull the DHCP data you will receive the modified DNS. But when out and about, everything will work as expected.
the latter, e.g. I'd assume an competent ISP with a large customer presence on the west coast would have DNS servers for their customers on the west coast, or just use anycast...
Yeah, not sure. I think most ISPs use just a couple of DNS servers for their entire network -- or at least that's the case here in the UK. But as you say, anycast might mean that those two IP addresses are actually represented by many servers.
I guess we'll need the input of someone who works at an ISP :)
