This article Thoughts on IPv6 Day (By James Seng) discusses the proposal to have a national IPv6 Flag Day where all Internet machines switch over to mandated support of IPv6. It is a good summary of the arguments of why this is not such a good idea just now. However, James is still advocating the deployment of IPv6 especially to enable p2p end-to-end applications and services. If we can demonstrate a certain level of IPv6 penetration, and good hardware support in routers, the switch over could be closer than we think.