Good to see MSI going mainstream - connecting with accountability and transparency issues.
It may be helpful to see Multi-stakeholder Initiatives as processes rather than platforms (although the platform is instrumental in process facilitation). Process facilitation work with multiple stakeholders has been described and studied for some time now - see for instance http://www.capacity.org/capacity/opencms/en/topics/multi-actor-engagement/index.html with reference to articles and books as far back as 2002, e.g. my favourite: “Multi-Stakeholder Processes for Governance and Sustainability: Beyond Deadlock and Conflict”, by Minu Hemmati, 2002 EarthScan
The Partnering initiative (TPI) http://thepartneringinitiative.org/ has developed standards for the practice of facilitating "collaborative partnerships" and provides training and professional accreditation.