Developers would provide:
Everyone would provide encouragement, support, their ideas, energy, and protocols. People who are not developers are invited to participate, contributing their enthusiasm, encouragement, ideas, publicity, translations, and art.
The way I imagine it, PICA would have an explicit membership. Like the IETF, only individuals are recognized. Corporations, governments, and organizations cannot be members. However, a sufficiently advanced artificial intelligence with a distinct identity could conceivably be a member. Anonymous individuals could be members, provided that the member meets the entrance vote.
Who would initially participate in PICA? I imagine most everybody here, interested in seeing these technologies go forward. I imagine Sean Palmer, Aaron Schwarts, and Cristopher Schmidt may be interested. I imagine Les Orchard may be interested. I imagine that various wiki developers may be interested- I have met some who are struggling to find acceptance and interoperability for their whatever-it-is that they have made. (I'm immediately thinking: "Xwiki has some really incredible stuff for making collaboratively produced data structures and databases a reality.")
Andy Updegrove claims: "I believe I've figured out how to make standards really, really exciting. Really." This sounds like exactly what we need here.
See PicaPeople for specific people joining PICA.