I agree that this mailing list is a reasonable place to discuss the interfaces.
Notes from the Architecture Summit are now up at https://www.mediawiki.org/wiki/Architecture_Summit_2014/TitleValue# . At yesterday's RFC review we agreed that we'd like to hold another one next week (will figure out a good date/time with Nik, Daniel, and the architects) and discuss TitleValue, see if there's anything that needs moving forward.
Sumana Harihareswara Engineering Community Manager Wikimedia Foundation