Using DNS to handle geo-aware redirection is commonly done, but is not always optimal.
The reason for this is that there's zero guarantee that the IP address in the DNS request is in any way correlated with the physical location of the user. Most times it might well be, but that's just a coincidence. What happens if the user is using OpenDNS - how do you redirect them then?
The "right" answer is application level redirection - have your servers look at the IP address of the actual HTTP request, and then redirect to another server (with a different name) if the client has hit the wrong server.
Google and a few others are currently proposing a new DNS extension at the IETF DNSEXT Working Group which allows open DNS services (such as OpenDNS) to tell Content Delivery Networks (e.g. Akamai) what your real address is, but it's quite controversial because of the privacy implications.