An additional 68m virtual reality headsets are set to hit the US by 2021 – fueling $4.6bn in revenue in that timeframe, according to a report out this week from UK consulting giant PwC. The analysts expect the consumer VR content market to reach $15.1bn globally by 2021 at a CAGR of 77%, with $8bn expected to be spent on VR video streaming over the five-year period – a figure which the forecast believes will overtake revenues for interactive experiences and games by 2019. The report does not elaborate on where the infrastructure will come from to drive this projected growth in the VR market. Operators and vendors are constantly announcing impressive pushes to upgrade fixed and mobile networks to…