I was a bit interested in this, so I checked what they changed from OpenWrt.
They seem to have started at approximately backfire r21824.
Added ISC DHCP (presumably for dhcpv6), packaging seems to be based on this http://code.google.com/p/nativev6/source/browse/#svn/packages-dev/dhcp4
Patched iproute2 to version 2.6.33. (not sure why they did not just change the URL)
Packaged sipcalc http://www.routemeister.net/projects/sipcalc
Patched kernel with 6rd and dslite.
Added the new package ipv6tunnel, which seems to be web interface / configuration of 6rd and dslite. It also contains a bit of duplicate code from other parts of OpenWrt.
Changed a bunch of defaults, mostly for IPv6.