OpenPublic Pantheon Hosting

I am about to build a couple sites for a Georgia non-profit, http://mystudentstudio.com/. The goal of this Drupal project consists of two parts: one is to implement the underlying system for our social network and student project management platform (thinking of using OpenAtrium here); the second is to build the system for how the Student Studio team will communicate to and collaborate with the public including schools, investors, parents etc (this is where I would use OpenPublic).