Confirming source-routed multicast is dead on the public Internet

[sean at donelan.com (Sean Donelan)]

Its tought to prove a negative. I'm extremely confident the answer is yes, 
public internet multicast is not viable. I did all the google searches, 
check all the usual CAIDA and ISP sites. IP Multicast is used on private 
enterprise networks, and some ISPs use it for some closed services.

I got sent back with a random comment from a senior official saying "but 
I heard different." I bit my tongue, and said I would double (now 
quadruple) check.

If any ISPs have working IP source-routed multicast on the public 
Internet that I missed, or what I got wrong.  That's what content 
distribution networks (cdn's) are for instead.