The cell tower business is in a state of flux. More and more mobile operators are divesting their passive infrastructure into joint ventures or fully independent towercos, changing the economics of the macro network and turning them away from real estate ownership towards an opex-heavy model. But for those towercos, there are many dilemmas as the mobile market changes. There is a process of consolidation going on, as the companies seek national and international scale. But this is not just about masts and sites. As the shape of the mobile network changes, the firms are also questioning how their entire business model may have to change in future. At the TowerXChange Meet-Up, a conference held in London last week, participants…