Namebench is a great utility to test your DNS performance against other publicly available DNS servers. It will run a multitude of DNS-related tests and give you back a recommended DNS configuration for your computer, based on the connection you are using when you run the test. The tool was created by a Google developer, but is not biased towards Google Public DNS. In my case, it suggested I use ‘The Planet” (company in Dallas) as my primary DNS provider.
The original project page is here:
It takes about 10 minutes to run, and can definitely be worth the trouble if you are having slow Internet browsing issues.