Several weeks ago the root servers were attacked. CNet is running a story that says Anycast played a role in preventing larger problems.
It would be interesting to see if all the root servers switch to Anycast. Where would the new distributed servers go? Does Verisign etc. own that many data centers? Or would they be in data centers and colo’s all over the world?
There is an interesting slideshow (PDF link) that discusses the effects of switching k-root to Anycast. It doesn’t really go into foiling DoS attacks though.