Hello Jari and others
Very good summary diagram indeed.
I think that we are still missing something from the high-level design space though. I do not know how to accurately or even descriptively name this category of approaches but there is a possibility to build on aggregation inside the network and between the ASs.
Examples of such approaches that are not visible in the diagram of yours are for example following
http://tools.ietf.org/html/draft-li-ispac-00
http://www.caida.org/publications/presentations/2003/internetworking03/atoms.internetworking03.pdf
The geographic aggregation based solutions discussed on this mailing list would belong to this category.
All the above proposals share in common the aspect that prefixes are aggregated and the participating ISPs/ASs need to collaborate to harvest the benefits.
For the shake of completeness we should also recognize that such approaches exits.
Best regards
Hannu