[russss]

> How do SpaceX communicate with the Dragon in orbit? Have they built their own global tracking/control network?

No, they're using the US government's TDRSS system (http://en.wikipedia.org/wiki/Tracking_and_Data_Relay_Satelli...), and I think they're also getting support from NASA's ground stations.

> Also, is sharing of ground facilities (fueling, launch, recovery) with other operators necessary for the business to be economic?

I don't think so - it seems like the cost of running the ground-based infrastructure is quite minimal compared to the actual operational costs of launching. Although SpaceX is using some of the original NASA/USAF infrastructure at Cape Canaveral and Vandenberg, it seems like they've built most of their facilities from scratch.