Marshall,
That's after 6 years.
I would be surprised if Shim6 going into actual deployed boxes was any faster. So, if Shim6 was finalized today, which it won't be, in 2010 we might have 70% deployment and in 2012 we might have 90% deployment.
I actually think that 2012 would be a more realistic date for 70% deployment of Shim6, given the lack of running code and a finalized protocol now.
In my opinion, that doesn't imply that Shim6 should be abandoned. But it does mean IMHO that regarding it as a means to spur IPv6 deployment is just not realistic.
Sorry, but I'm just not buying the analogy. The market drivers for IGMP are somewhat smaller than they are for IPv6. Yes, it would take a couple of years for Shim6 to be implemented and depending on where we hit Redmond's release cycle, actually penetrate a significant number of hosts. 6 years is probably long, and definitely long if we get a confluence of panic about the death of v4 plus a strong endorsement about Shim6 from the IETF. Consider that the IETF *could* conceivably require every compliant v6 implementation to include it. I grant that that's unlikely and some lesser endorsement is probably more reasonable, but I don't think that you should underestimate the capability of the IETF/ISP/vendor/host community to act a bit more quickly, if there is sufficient motivation. I suggest that we compromise, split the difference and swag it at 4 years. Tony