Read an article about this this morning, was just announced today.
I have started to use it on my 3 mobile broadband dongle and everything seems to load much 'zippier'.! Had tried the OpenDNS.com servers to help things along from the seemingly congested ISP offering... not to much avail. (perhaps a victim of their own success?)
If they make any difference to you is subjective to what you are using currently traffic/ traffic shaping etc... Google say items such as 'prefetching' and massive high level server farms will help move things along a wee bit faster.
DNS Servers are at:
184.108.40.206 and 220.127.116.11
See a Google-based overview from 'go to deal' button
(lol) A better connecting web improves google's margins after all !?