You flagged this as "DNS". DNS is sometimes called the 'poor man's load balancer".
The DNS servers themselves are inherently redundant, but their role as a load balancer does not offer a redundant solution for the web servers since no monitoring is built-in to take a node out of rotation when it fails. You need to write your own, and even then DNS caching keeps it from an immediate update during failures.
However, a hardware or software load balancer of some sort is usually better. It gives faster failover times, better monitoring, and much more control than DNS does.
Load Balancers will generally work in pairs and have a virtual IP that floats between them. If one fails, the other load balancer will take over IP address. That avoids a single point of contact.
My recommendation is to research load balancers more to see what you're comfortable with. For example, would you use a hardware load balancer, does your data center provider have a solution that you can use, or would you want to consider a Linux based or Microsoft based solution that you could get up to speed on quickly, depending on your expertise.
If you truly want data center redundancy then you will need to depend on BGP or DNS. There are some DNS services that offer this as a service: http://edgedirector.com/ and http://www.autofailover.com/ are two examples.