Let me start by saying I am a bit tired, so I may well just be missing something. It seems that ICMP traffic is not making it outside of the HE.Net network. Here is a sample trace showing what i am referring to.
Tracing route to fd-fp3.wg1.b.yahoo.com [2001:4998:58:c02::a9]
over a maximum of 30 hops:
1 2 ms 4 ms 2 ms 2001:470:8:961:x:x:x:1
2 70 ms 51 ms 52 ms angelou-1.tunnel.tserv13.ash1.ipv6.he.net [2001:470:7:961::1]
3 50 ms 51 ms 44 ms ge5-4.core1.ash1.he.net [2001:470:0:90::1]
4 * * * Request timed out.
5 * * * Request timed out.
It does not seem to matter the target, the trace dies at hop 3. This seems to suggest to me that I am setup correctly on my end as it looks as though I am making it into the ne.net network. I also did a couple IPv6 test webpages which all seem to indicate that ICMP is being filtered. Was there perhaps a change I was unaware of?