So, in any case I would not use site-locals for communication between sites. There are ideas floating around to make them globally unique, but this is for the purpose of avoiding renumbering when merging sites and not to provide site-to-site communication. Global addresses are required for that purpose, whether or not they are publicly routed or not.
Site-locals also break a number of applications, and create many problems. Which is why people argued to depracte them. But they are technically there as you say. But let's not spill the ipv6 deabte over here...:-)
There are several proposals to provide PI-like addresses that are moving forward though.
Besides your and Iljitsch draft and Tony Hains draft I haven't seen anything new? And both of these have been there for quite some time with no further discussions so I am not really sure which ones you mean? - kurtis -