For those of you not aware of this, the IEA Task 37 website has a number of useful resources, not least of which are the Country Reports which summarise activity in member countries over the given period.
Task 37 members recently published an annual summary of their Country Reports for 2014. The individual country reports include information on the number of biogas plants in operation, biogas production data, biogas utilisation, number of upgrading plants, number of vehicles using biomethane as fuel, details of financial support mechanisms and some information on key national research and development projects.