Half an Hour: What Makes a MOOC Massive?: Responding to a LinkedIn Discussion .
When people ask me what makes a MOOC 'massive' I respond in terms of the *capacity* of the MOOC rather than any absolute numbers.
In particular, my focus is on the development of a network structure, as opposed to a group structure, to manage the course. In a network structure there isn't any central focus, for example, a central discussion. Different people discuss different topics in different places (Twitter, Google Groups, Facebook, whatever) as they wish.
Additionally, my understanding is that for the course to be a *course* it has to be more than just a broadcast. Otherwise, 'Adventure Planet' is a MOOC. Or National Geographic Magazine is a MOOC. A course actually requires these interactive and skills development activities, rather than simply consumption of content.
So what is essential to a course being a *massive* open online course, therefore, is that it is not based in a particular environment, isn't characterized by its use of a single platform, but rather by the capacity of the technology supporting the course to enable and engage conversations and activities across multiple platforms.