Hey all,
Not so much a question as an FYI (since this drove me nuts until I figured this out):
The IPv6 Portscan at http://www.tunnelbroker.net/portscan.php originates from 2001:470:0:64::2, not 2001:470:0:aa::2 as shown on the page.
The nmap "ping probes" that are run to test connectivity without -PN are not ICMPv6, but rather TCP ports 80 and 443. This is due to an inherent limitation in nmap.
Hope this helps!